Read in data

Check data normality

The data is not normally distributed. Plus it is count data. t-test assumes that data is normally distributed, and comparing the means of counts data is also not appropriate, we can check the incidence rate ratio for comparison of business_days_until_appointment among the categories of insurance. Better to use Poisson regression.

## Starting normality check and summary calculation for variable: business_days_until_appointment
## Data extracted for variable: business_days_until_appointment
## Shapiro-Wilk normality test completed with p-value: 0.000000000000000000000000000000023172839871129
## The p-value is less than or equal to 0.05, indicating that the data is not normally distributed.
## Histogram with Density Plot created.
## Q-Q Plot created.

## Data is NOT normally distributed. Use non-parametric measures like median: 12, IQR: 15
## $median
## [1] 12
## 
## $iqr
## [1] 15
## Summary calculation completed for variable: business_days_until_appointment

## $median
## [1] 12
## 
## $iqr
## [1] 15

Simple poisson regression is more appropriate than Kruskall-Wallis as we have counts data in response. Since, Kruskal-wallis is for ordinal or continuous response variable. Poisson regression will give more information about each level of insurance influencing the business_days_until_appointment, whereas Kruskal-wallis just presenting if insurance as a variable is signficant predictor of response.

## 
## Call:
## glm(formula = business_days_until_appointment ~ as.factor(insurance), 
##     family = "poisson", data = df)
## 
## Coefficients:
##                              Estimate Std. Error z value            Pr(>|z|)
## (Intercept)                   2.73877    0.01315  208.31 <0.0000000000000002
## as.factor(insurance)Medicaid  0.26747    0.02013   13.29 <0.0000000000000002
##                                 
## (Intercept)                  ***
## as.factor(insurance)Medicaid ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## (Dispersion parameter for poisson family taken to be 1)
## 
##     Null deviance: 9082.3  on 586  degrees of freedom
## Residual deviance: 8908.5  on 585  degrees of freedom
##   (456 observations deleted due to missingness)
## AIC: 11375
## 
## Number of Fisher Scoring iterations: 5
## The baseline rate of business_days_until_appointment (intercept) is estimated to be 15.47 times the reference category, with a 95% confidence interval ranging from 15.07 to 15.87 . For Medicaid compared to the reference category (BCBS), the rate of business_days_until_appointment is approximately 1.31 times higher . The 95% confidence interval for this estimate ranges between 1.26 and 1.36 , meaning that the waiting time for an appointment is estimated to be about 1.31 times longer for Medicaid patients than for those with BCBS insurance.

Quality Check the Data

Are there any physicians included more than twice?

Included More than Twice
id_number physician_information N
NA NA NA
———: :——————— –:

Variables of those physicians included more than twice?

## File saved to: ortho_sports_med/Figures/quality_check_table2.csv
Variables of Physicians Included More Than Twice
id_number physician_information reason_for_exclusions insurance business_days_until_appointment
NA NA NA NA NA
———: :——————— :——————— :——— ——————————-:

Filter data so there is only one NPI per insurance type

Find physicians called more than once

id_numbers called more than twice
physician_information calls_count
NA NA
:——————— ———–:

Do they have exclusion and have a business_days_until_appointment >0?

## File saved to: ortho_sports_med/Figures/discrepancy_rows.csv

Do they have business_days_until_appointment >0 but are an excluded category?

Records with Appointments but in Excluded Category
physician_information id_number notes reason_for_exclusions business_days_until_appointment
NA NA NA NA NA
:——————— ———: :—– :——————— ——————————-:

Do they have NA for business_days_until_appointment but are “Included” in the Reasons for exclusion category?

Included Records with NA for Appointments
physician_information id_number notes reason_for_exclusions business_days_until_appointment
1048, Dr. Dhar, 914-686-0111, Medicaid, HIP scenario, New York, Eastern Time Zone 1048 NA Able to contact NA
1044, Dr. Wind, 716-204-3200, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 1044 correct number Able to contact NA
1038, Dr. Mealer, 310-546-3461, Medicaid, HIP scenario, California, Pacific Time Zone 1038 initial call was fine with no hold and after stating they had medicaid they said they needed to verify and placed me on a 9 min hold Able to contact NA
1035, Dr. Greer, 843-652-8160, Blue Cross/Blue Shield, SHOULDER scenario, South Carolina, Eastern Time Zone 1035 NA Able to contact NA
1034, Dr. Sterett, 970-476-7220, Medicaid, KNEE scenario, Colorado, Mountain Time Zone 1034 NA Able to contact NA
1030, Dr. Montgomery, 415-668-1000, Medicaid, KNEE scenario, California, Pacific Time Zone 1030 The number provided is a direct line to a hospital operator. The correct number is 415-221-0665. Able to contact NA
1022, Dr. Stetson, 818-848-3030, Medicaid, KNEE scenario, California, Pacific Time Zone 1022 NA Able to contact NA
1020, Dr. Kramer, 949-720-1944, Medicaid, HIP scenario, California, Pacific Time Zone 1020 NA Able to contact NA
1018, Dr. Hovis, 865-251-3030, Medicaid, KNEE scenario, Tennessee, Central Time Zone 1018 dont take any medicaid Able to contact NA
1012, Dr. Irion, 337-635-3052, Medicaid, KNEE scenario, Louisiana, Central Time Zone 1012 3186353052 Able to contact NA
1000, Dr. Nemickas, 847-336-3335, Medicaid, KNEE scenario, Illinois, Central Time Zone 1000 NA Able to contact NA
996, Dr. Johnson, 952-831-8742, Medicaid, HIP scenario, Minnesota, Central Time Zone 996 Cannot tell me if Medicaid is taken here or not. Transferred me to billing who gave me a billing number/ID for me to call sister’s insurance and verify if they were within network. Able to contact NA
985, Dr. Berney, 808-242-6464, Blue Cross/Blue Shield, HIP scenario, Hawaii, Hawaii-Aleutian Time Zone 985 Does not operate on hip Able to contact NA
974, Dr. Chambers, 843-353-3460, Medicaid, KNEE scenario, South Carolina, Eastern Time Zone 974 NA Able to contact NA
972, Dr. Winters, 407-421-2163, Medicaid, KNEE scenario, Florida, Eastern Time Zone 972 wrong number correct number: (407) 649-1097 Do NOT accept any medicaid Able to contact NA
968, Dr. Tingle, 847-870-4200, Medicaid, KNEE scenario, Illinois, Central Time Zone 968 NA Able to contact NA
966, Dr. Mann, 303-665-2603, Medicaid, KNEE scenario, Colorado, Mountain Time Zone 966 NA Able to contact NA
962, Dr. Gertel, 414-276-6000, Medicaid, SHOULDER scenario, Wisconsin, Central Time Zone 962 NA Able to contact NA
948, Dr. Cherney, 631-444-4233, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 948 They have a medicaid clinic that Dr. Cherney will sometimes help with but it’s more like a walk in thing and you’re not guaranteed to see him. Able to contact NA
946, Dr. Meier, 310-777-7845, Medicaid, KNEE scenario, California, Pacific Time Zone 946 Cash only Able to contact NA
944, Dr. Gorin, 305-392-1212, Medicaid, HIP scenario, Florida, Eastern Time Zone 944 NA Able to contact NA
940, Dr. Sandoval, 903-870-7936, Medicaid, SHOULDER scenario, Texas, Central Time Zone 940 NA Able to contact NA
920, Dr. Rajan, 551-999-6433, Medicaid, HIP scenario, New Jersey, Eastern Time Zone 920 NA Able to contact NA
912, Dr. Devine, 805-541-4600, Medicaid, HIP scenario, California, Pacific Time Zone 912 NA Able to contact NA
910, Dr. Silas, 386-274-5252, Medicaid, HIP scenario, Florida, Eastern Time Zone 910 NA Able to contact NA
908, Dr. Powell, 818-570-5000, Medicaid, KNEE scenario, California, Pacific Time Zone 908 NA Able to contact NA
902, Dr. Bansal, 718-515-9800, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 902 NA Able to contact NA
898, Dr. Taylor, 203-705-0750, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 898 correct number Able to contact NA
894, Dr. Pitts, 314-569-0616, Medicaid, HIP scenario, Missouri, Central Time Zone 894 NA Able to contact NA
874, Dr. Scheinberg, 214-227-6861, Medicaid, SHOULDER scenario, Texas, Central Time Zone 874 Medicaid not accepted as primary insurance Able to contact NA
872, Dr. Jones, 901-641-3000, Medicaid, HIP scenario, Tennessee, Central Time Zone 872 dont accept any medicaid Able to contact NA
854, Dr. Kelly, 770-421-8005, Medicaid, KNEE scenario, Georgia, Eastern Time Zone 854 NA Able to contact NA
838, Dr. Greenfield, 858-270-4420, Medicaid, HIP scenario, California, Pacific Time Zone 838 NA Able to contact NA
834, Dr. Gayle, 650-934-7111, Medicaid, HIP scenario, California, Pacific Time Zone 834 NA Able to contact NA
830, Dr. Kinnard, 301-646-1006, Medicaid, HIP scenario, Maryland, Eastern Time Zone 830 NA Able to contact NA
824, Dr. McCormack, 855-321-6784, Medicaid, HIP scenario, New York, Eastern Time Zone 824 do NOT take ANY medicaid Able to contact NA
822, Dr. Bartz, 214-256-3778, Medicaid, SHOULDER scenario, Texas, Central Time Zone 822 NA Able to contact NA
820, Dr. Whitehead, 601-268-5630, Medicaid, KNEE scenario, Mississippi, Central Time Zone 820 correct number Able to contact NA
814, Dr. Risinger, 860-525-4469, Medicaid, KNEE scenario, Connecticut, Eastern Time Zone 814 Midlevels accept medicaid but Dr. Risinger does not. Able to contact NA
812, Dr. Troop, 972-250-5700, Medicaid, SHOULDER scenario, Texas, Central Time Zone 812 NA Able to contact NA
810, Dr. Pandarinath, 301-530-1010, Medicaid, HIP scenario, District of Columbia, NA 810 accept medicaid only as secondary insurance not as primary Able to contact NA
806, Dr. Atluri, 847-956-0099, Medicaid, SHOULDER scenario, Illinois, Central Time Zone 806 NA Able to contact NA
804, Dr. Vo, 863-680-7214, Medicaid, SHOULDER scenario, Florida, Eastern Time Zone 804 NA Able to contact NA
790, Dr. Hester, 859-258-8575, Medicaid, KNEE scenario, Kentucky, Eastern Time Zone 790 NA Able to contact NA
788, Dr. Simonian, 559-439-7633, Medicaid, KNEE scenario, California, Pacific Time Zone 788 NA Able to contact NA
786, Dr. Sallay, 317-708-3400, Medicaid, KNEE scenario, Indiana, Eastern Time Zone 786 correct number Able to contact NA
784, Dr. Chang, 615-322-5000, Medicaid, HIP scenario, Colorado, Mountain Time Zone 784 615-322-4500 Called the vanderbilt center instead (no longer with steadman), above info corresponds to that. They only accept “certain kinds of Medicaid” and need more info. Able to contact NA
778, Dr. McGahan, 415-900-3000, Medicaid, KNEE scenario, California, Pacific Time Zone 778 NA Able to contact NA
772, Dr. Drew, 337-703-3201, Medicaid, KNEE scenario, Louisiana, Central Time Zone 772 NA Able to contact NA
770, Dr. Ilahi, 713-610-4260, Medicaid, SHOULDER scenario, Texas, Central Time Zone 770 NA Able to contact NA
752, Dr. ElAttrache, 310-665-7151, Medicaid, KNEE scenario, California, Pacific Time Zone 752 NA Able to contact NA
748, Dr. Kasim, 732-548-7332, Medicaid, HIP scenario, New Jersey, Eastern Time Zone 748 correct number Able to contact NA
746, Dr. Suri, 504-736-4800, Medicaid, HIP scenario, Louisiana, Central Time Zone 746 Unable to provide an appointment date without creating a chart. Able to contact NA
736, Dr. Havig, 239-325-1135, Medicaid, KNEE scenario, Florida, Eastern Time Zone 736 NA Able to contact NA
732, Dr. Marandola, 949-348-4000, Medicaid, HIP scenario, California, Pacific Time Zone 732 NA Able to contact NA
726, Dr. Mariorenzi, 401-944-3800, Medicaid, KNEE scenario, Rhode Island, Eastern Time Zone 726 first call was on hold for more than 5 min. second call went through. Able to contact NA
722, Dr. Lastihenos, 631-665-8790, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 722 NA Able to contact NA
720, Dr. Sidor, 856-273-8900, Medicaid, SHOULDER scenario, New Jersey, Eastern Time Zone 720 NA Able to contact NA
716, Dr. Shindle, 673-694-2690, Medicaid, SHOULDER scenario, New Jersey, Eastern Time Zone 716 correct number: 973-694-2690 DO NOT ACCEPT MEDICAID AT ALL Able to contact NA
714, Dr. Gustavel, 208-957-7400, Medicaid, HIP scenario, Idaho, Mountain Time Zone 714 NA Able to contact NA
710, Dr. Battaglia, 425-429-7573, Medicaid, SHOULDER scenario, Washington, Pacific Time Zone 710 NA Able to contact NA
700, Dr. Purnell, 209-638-5330, Medicaid, KNEE scenario, California, Pacific Time Zone 700 NA Able to contact NA
690, Dr. Eslava, 251-450-2746, Medicaid, KNEE scenario, Alabama, Central Time Zone 690 only accept medicaid for children <18 Able to contact NA
688, Dr. Brager, 734-464-0400, Medicaid, SHOULDER scenario, Michigan, Eastern Time Zone 688 NA Able to contact NA
668, Dr. Provencher, 970-476-1100, Medicaid, KNEE scenario, Colorado, Mountain Time Zone 668 They don’t accept all of Colorado Medicaid unless you live in Vail county. I didn’t know that and said my sister lives in Denver, and so she said I’d only be able to see Dr. Godin and wouldn’t give me a date for Dr. Provencher. Able to contact NA
666, Dr. Diesselhorst, 405-463-3337, Medicaid, HIP scenario, Oklahoma, Central Time Zone 666 first call went to an answering service. Able to contact NA
656, Dr. Allegra, 732-888-8388, Medicaid, HIP scenario, New Jersey, Eastern Time Zone 656 NA Able to contact NA
650, Dr. Geyer, 512-863-4563, Medicaid, HIP scenario, Texas, Central Time Zone 650 Dr Geyer’s clinic accepts certain kinds of Medicaid, unsure how to label this. Able to contact NA
648, Dr. Provenzano, 713-464-0077, Medicaid, SHOULDER scenario, Texas, Central Time Zone 648 NA Able to contact NA
642, Dr. Billante, 512-509-0200, Medicaid, SHOULDER scenario, Texas, Central Time Zone 642 correct number Able to contact NA
636, Dr. Trautmann, 787-274-0822, Medicaid, KNEE scenario, Puerto Rico, NA 636 Location was in puerto rico, she said they dont take medicaid, but not sure if medicaid extends to puerto rico to begin with, might want to check. Able to contact NA
634, Dr. Wilson, 318-299-6334, Medicaid, HIP scenario, Louisiana, Central Time Zone 634 NA Able to contact NA
632, Dr. Pinto, 734-593-5700, Medicaid, SHOULDER scenario, Michigan, Eastern Time Zone 632 Scheduler is out for Dr. pinto, cannot find appt times. Current person is ‘pretty sure’ he takes ‘straight medicaid’ with ‘the green card’. Able to contact NA
626, Dr. Greenfield, 602-298-1188, Medicaid, KNEE scenario, Arizona, Mountain Time Zone 626 NA Able to contact NA
620, Dr. Davidson, 503-661-5388, Medicaid, SHOULDER scenario, Oregon, Pacific Time Zone 620 NA Able to contact NA
618, Dr. York, 404-355-0743, Medicaid, KNEE scenario, Georgia, Eastern Time Zone 618 NA Able to contact NA
602, Dr. Lowery, 614-729-6900, Medicaid, KNEE scenario, Ohio, Eastern Time Zone 602 NA Able to contact NA
596, Dr. Griffin, 678-732-1336, Medicaid, KNEE scenario, Georgia, Eastern Time Zone 596 NA Able to contact NA
594, Dr. Kim, 650-756-5630, Medicaid, KNEE scenario, California, Pacific Time Zone 594 They do not accept Medicaid as a primary insurance but will accept it as a secondary Able to contact NA
592, Dr. Popovitz, 212-759-4553, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 592 NA Able to contact NA
566, Dr. Roth, 650-853-2943, Medicaid, KNEE scenario, California, Pacific Time Zone 566 NA Able to contact NA
559, Dr. Plancher, 212-876-5200, Blue Cross/Blue Shield, SHOULDER scenario, New York, Eastern Time Zone 559 Dr. Plancher doesn’t take any insurance (he’s out of pocket only). Able to contact NA
554, Dr. Warnock, 281-807-4380, Medicaid, SHOULDER scenario, Texas, Central Time Zone 554 NA Able to contact NA
550, Dr. Chan, 415-668-8010, Medicaid, HIP scenario, California, Pacific Time Zone 550 NA Able to contact NA
544, Dr. Sutton, 203-705-0725, Medicaid, HIP scenario, New York, Eastern Time Zone 544 NA Able to contact NA
542, Dr. Schneider, 212-434-6880, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 542 NA Able to contact NA
534, Dr. Steinvurzel, 516-773-7500, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 534 NA Able to contact NA
528, Dr. Harris, 713-441-8393, Medicaid, HIP scenario, Texas, Central Time Zone 528 NA Able to contact NA
524, Dr. Milne, 817-335-4316, Medicaid, HIP scenario, Texas, Central Time Zone 524 NA Able to contact NA
510, Dr. Loewen, 620-259-2325, Medicaid, HIP scenario, Kansas, Central Time Zone 510 correct number Able to contact NA
508, Dr. Gill, 214-890-0906, Medicaid, SHOULDER scenario, Texas, Central Time Zone 508 they do NOT accept ANY medicaid Able to contact NA
500, Dr. Mehalik, 239-482-2663, Medicaid, KNEE scenario, Florida, Eastern Time Zone 500 NA Able to contact NA
486, Dr. Carlisle, 913-319-7686, Medicaid, HIP scenario, Kansas, Central Time Zone 486 NA Able to contact NA
478, Dr. Tanksley, 936-291-3459, Medicaid, HIP scenario, Texas, Central Time Zone 478 NA Able to contact NA
476, Dr. Zavala, 972-771-8111, Medicaid, SHOULDER scenario, Texas, Central Time Zone 476 NA Able to contact NA
462, Dr. Berg, 703-214-7437, Medicaid, SHOULDER scenario, Virginia, Eastern Time Zone 462 NA Able to contact NA
456, Dr. Michaelson, 248-349-7015, Medicaid, SHOULDER scenario, Michigan, Eastern Time Zone 456 NA Able to contact NA
446, Dr. Jancosko, 412-720-9128, Medicaid, SHOULDER scenario, Maryland, Eastern Time Zone 446 Correct number is 410-820-8226. They don’t accept all forms of Medicaid (like I said the normal Maryland one and they said that they don’t take that one, otherwise they are scheduling out to two weeks from now) Able to contact NA
440, Dr. Browdy, 314-991-2150, Medicaid, SHOULDER scenario, Missouri, Central Time Zone 440 NA Able to contact NA
434, Dr. Hommen, 305-520-5625, Medicaid, HIP scenario, Florida, Eastern Time Zone 434 NA Able to contact NA
432, Dr. Genuario, 303-694-3333, Medicaid, HIP scenario, Colorado, Mountain Time Zone 432 NA Able to contact NA
431, Dr. Genuario, 303-694-3333, Blue Cross/Blue Shield, HIP scenario, Colorado, Mountain Time Zone 431 Just immediately hung up when they couldn’t find her information Able to contact NA
430, Dr. Cahill, 201-379-6221, Medicaid, HIP scenario, New Jersey, Eastern Time Zone 430 NA Able to contact NA
420, Dr. Marzec, 631-422-9530, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 420 do NOT accept medicaid Able to contact NA
418, Dr. Guerra, 239-593-3500, Medicaid, KNEE scenario, Florida, Eastern Time Zone 418 NA Able to contact NA
414, Dr. Emanuel, 314-997-1777, Medicaid, SHOULDER scenario, Missouri, Central Time Zone 414 NA Able to contact NA
410, Dr. Crowther, 919-322-8619, Medicaid, SHOULDER scenario, North Carolina, Eastern Time Zone 410 do not take medicaid as a primary Able to contact NA
400, Dr. Mitchell, 352-323-4000, Medicaid, KNEE scenario, Florida, Eastern Time Zone 400 NA Able to contact NA
396, Dr. Gialamas, 949-661-2423, Medicaid, HIP scenario, California, Pacific Time Zone 396 NA Able to contact NA
394, Dr. Gallick, 908-686-6665, Medicaid, SHOULDER scenario, New Jersey, Eastern Time Zone 394 NA Able to contact NA
376, Dr. Branche, 703-769-8480, Medicaid, SHOULDER scenario, Virginia, Eastern Time Zone 376 NA Able to contact NA
374, Dr. Gilyard, 248-206-2990, Medicaid, SHOULDER scenario, Michigan, Eastern Time Zone 374 Correct Number: 248-792-9496 Ext 5 Able to contact NA
364, Dr. Giacobetti, 424-220-4400, Medicaid, HIP scenario, California, Pacific Time Zone 364 don’t accept any medicaid and no shame at all Able to contact NA
356, Dr. Moya-Huff, 954-392-1725, Medicaid, KNEE scenario, Florida, Eastern Time Zone 356 NA Able to contact NA
350, Dr. Lopez, 877-945-9090, Medicaid, HIP scenario, Illinois, Central Time Zone 350 NA Able to contact NA
346, Dr. Yoldas, 954-866-9699, Medicaid, KNEE scenario, Florida, Eastern Time Zone 346 dont accept any medicaid Able to contact NA
342, Dr. Price, 516-874-4543, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 342 do NOT accept medicaid. none of their doctors accept medicaid Able to contact NA
340, Dr. Freeman, 516-789-2396, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 340 Does not take pure (?) New York Medicaid Able to contact NA
334, Dr. Putterman, 516-536-2800, Medicaid, KNEE scenario, New York, Eastern Time Zone 334 doesnt take any medicaid Able to contact NA
324, Dr. Chen, 408-782-4060, Medicaid, HIP scenario, California, Pacific Time Zone 324 NA Able to contact NA
310, Dr. Freedberg, 480-558-3744, Medicaid, KNEE scenario, Arizona, Mountain Time Zone 310 NA Able to contact NA
308, Dr. Floyd, 432-520-3020, Medicaid, KNEE scenario, Texas, Central Time Zone 308 NA Able to contact NA
306, Dr. Heitman, 718-576-6822, Medicaid, HIP scenario, New Jersey, Eastern Time Zone 306 NA Able to contact NA
304, Dr. Striplin, 310-784-2355, Medicaid, HIP scenario, California, Pacific Time Zone 304 don’t take any medical Able to contact NA
300, Dr. Ochiai, 703-525-2200, Medicaid, HIP scenario, Virginia, Eastern Time Zone 300 NA Able to contact NA
296, Dr. Romero, 925-757-0800, Medicaid, HIP scenario, California, Pacific Time Zone 296 NA Able to contact NA
292, Dr. Starch, 830-341-1386, Medicaid, SHOULDER scenario, Texas, Central Time Zone 292 NA Able to contact NA
290, Dr. Elias, 985-625-2200, Medicaid, KNEE scenario, Louisiana, Central Time Zone 290 NA Able to contact NA
288, Dr. Ryan, 706-549-1663, Medicaid, HIP scenario, Georgia, Eastern Time Zone 288 NA Able to contact NA
284, Dr. Rudman, 201-447-1188, Medicaid, SHOULDER scenario, New Jersey, Eastern Time Zone 284 NA Able to contact NA
278, Dr. Burt, 815-267-8825, Medicaid, KNEE scenario, Illinois, Central Time Zone 278 NA Able to contact NA
274, Dr. Smink, 301-589-3324, Medicaid, SHOULDER scenario, Maryland, Eastern Time Zone 274 NA Able to contact NA
272, Dr. Lintner, 713-441-3560, Medicaid, SHOULDER scenario, Texas, Central Time Zone 272 NA Able to contact NA
270, Dr. Gonzalez, 210-640-9048, Medicaid, SHOULDER scenario, Texas, Central Time Zone 270 correct number Able to contact NA
252, Dr. Deramo, 201-470-6977, Medicaid, KNEE scenario, New Jersey, Eastern Time Zone 252 Correct phone number: 201-430-8266 Able to contact NA
250, Dr. Johnson, 703-729-5010, Medicaid, SHOULDER scenario, Virginia, Eastern Time Zone 250 NA Able to contact NA
231, Dr. Byck, 303-662-8250, Blue Cross/Blue Shield, SHOULDER scenario, Colorado, Mountain Time Zone 231 NA Able to contact NA
228, Dr. Veltri, 860-454-0527, Medicaid, KNEE scenario, Connecticut, Eastern Time Zone 228 The office will call back with an appointment if Dr. Veltri agrees to see it. I will update the appt date when I hear back. Able to contact NA
224, Dr. Kalbac, 305-595-2414, Medicaid, KNEE scenario, Florida, Eastern Time Zone 224 NA Able to contact NA
220, Dr. Tensmeyer, 801-543-6775, Medicaid, HIP scenario, Utah, Mountain Time Zone 220 NA Able to contact NA
200, Dr. Rios, 860-549-8295, Medicaid, KNEE scenario, Connecticut, Eastern Time Zone 200 Only accepting pediatric medicaid Able to contact NA
188, Dr. Wong, 817-676-9046, Medicaid, KNEE scenario, Texas, Central Time Zone 188 NA Able to contact NA
186, Dr. Mancuso, 610-376-8671, Medicaid, KNEE scenario, Pennsylvania, Eastern Time Zone 186 do NOT accept medicaid (PA access card) Able to contact NA
176, Dr. Brusalis, 517-743-3036, Medicaid, SHOULDER scenario, Illinois, Central Time Zone 176 HSS not Rush 516-743-3036 Able to contact NA
172, Dr. Alexander, 951-335-5785, Medicaid, HIP scenario, California, Pacific Time Zone 172 didn’t take state medical plan Able to contact NA
170, Dr. Corradino, 844-300-4677, Medicaid, SHOULDER scenario, New Jersey, Eastern Time Zone 170 NA Able to contact NA
142, Dr. Tandron, 904-346-3465, Medicaid, KNEE scenario, Florida, Eastern Time Zone 142 NA Able to contact NA
140, Dr. George, 713-572-0030, Medicaid, KNEE scenario, Texas, Central Time Zone 140 NA Able to contact NA
138, Dr. Morris, 770-962-4300, Medicaid, KNEE scenario, Georgia, Eastern Time Zone 138 Do not accept medicaid as primary insurance Literally 5 transfers lmao Able to contact NA
128, Dr. McConnell, 843-284-5200, Medicaid, KNEE scenario, South Carolina, Eastern Time Zone 128 NA Able to contact NA
116, Dr. Snow, 972-346-1998, Medicaid, SHOULDER scenario, Texas, Central Time Zone 116 NA Able to contact NA
114, Dr. Gruber, 602-734-1834, Medicaid, KNEE scenario, Arizona, Mountain Time Zone 114 NA Able to contact NA
92, Dr. Mandelbaum, 310-829-2663, Medicaid, KNEE scenario, California, Pacific Time Zone 92 NA Able to contact NA
84, Dr. Rask, 503-648-0803, Medicaid, SHOULDER scenario, Oregon, Pacific Time Zone 84 correct number Able to contact NA
82, Dr. Estes, 205-939-0447, Medicaid, HIP scenario, Alabama, Central Time Zone 82 NA Able to contact NA
70, Dr. Scillia, 973-446-7500, Medicaid, HIP scenario, New Jersey, Eastern Time Zone 70 NA Able to contact NA
66, Dr. Stoeckl, 716-250-9999, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 66 do NOT accept ANY medicaid Able to contact NA
64, Dr. Whaley, 210-293-2663, Medicaid, SHOULDER scenario, Texas, Central Time Zone 64 NA Able to contact NA
54, Dr. Weiss, 310-652-1800, Medicaid, HIP scenario, California, Pacific Time Zone 54 NA Able to contact NA
48, Dr. Scott, 509-466-6393, Medicaid, SHOULDER scenario, Washington, Pacific Time Zone 48 NA Able to contact NA
36, Dr. Savage, 251-928-2401, Medicaid, HIP scenario, Alabama, Central Time Zone 36 NA Able to contact NA
32, Dr. Strizak, 949-582-5934, Medicaid, KNEE scenario, California, Pacific Time Zone 32 NA Able to contact NA
18, Dr. Kouyoumjian, 972-492-1334, Medicaid, HIP scenario, Texas, Central Time Zone 18 NA Able to contact NA
14, Dr. Cohen, 646-681-2681, Medicaid, SHOULDER scenario, New York, Eastern Time Zone 14 correct number Able to contact NA
10, Dr. Schachter, 203-877-5522, Medicaid, KNEE scenario, Connecticut, Eastern Time Zone 10 NA Able to contact NA
4, Dr. Binder, 504-309-6500, Medicaid, KNEE scenario, Louisiana, Central Time Zone 4 NA Able to contact NA

Results

Insurance Acceptance Rates

Steps to Calculate Medicaid Acceptance Rate

These acceptance rates reflect the proportion of physicians who were successfully contacted, accepted the respective insurance, and provided an appointment to the patient.

Medicaid Acceptance Rate: Out of the total number of physicians assigned Medicaid insurance (520), 210 physicians accepted Medicaid and provided an appointment, resulting in an acceptance rate of 56.1%.

Blue Cross/Blue Shield Acceptance Rate: Among the physicians assigned Blue Cross/Blue Shield insurance (523), 369 accepted this insurance and provided an appointment, yielding an acceptance rate of 97.4%.

Appointment Accessibility

## Our sample included 1043 calls to physician offices from 49 states, including the District of Columbia, excluding Delaware and South Dakota . We made calls to 523 unique physicians that accepted Blue Cross/Blue Shield. Two Hundred Ten physician offices accepted Medicaid, giving a 56.1 % Medicaid acceptance rate for Orthopedic Sports Medicine practices (n = 210 /N = 374 ).  Physicians offices accepted Blue Cross/Blue Shield at a rate of 97.4 % (n = 369 /N = 379 ).

Univariate Analysis

The median physician age was 55(IQR 25th percentile 48 to 75th percentile 62).

Gender Distribution calculations

## In our dataset, the most common physician gender was Male (n = 985/N = 1,043, 94.4%). The predominant subspecialty observed was Sports Medicine Orthopaedics (n = 1,043/N = 1,043, 100.0%). Additionally, the most prevalent professional qualification was MD (n = 1,021/N = 1,043, 97.9%).

Logistic Regression to Accept Medicaid

Significant Predictors for Logistic Regression: 0.2

Variable P_Value Formatted_P_Value
call_time_minutes 0.0000098 <0.01
academic 0.0230164 0.02
age 0.0311335 0.03
number_of_transfers 0.0362681 0.04
Variable P_Value Formatted_P_Value Direction
call_time_minutes 0.0000098 <0.01 Higher
academic 0.0230164 0.02 Lower
age 0.0311335 0.03 Lower
number_of_transfers 0.0362681 0.04 Higher
## call_time_minutes Higher (p = <0.01) and academic Lower (p = 0.02) and age Lower (p = 0.03) and number_of_transfers Higher (p = 0.04)

Variable Selection

Wait Time with single predictor

Wait Times for All Insurances
Median_business_days_until_appointment Q1 Q3
12 6 21

The median wait time across all insurance was 12 business days, with an interquartile range (IQR) of 6 to 21.

## SHOULDER scenario scenario patients experienced a 6.48 % longer wait for a new patient appointment compared to HIP scenario scenario patients (Incidence Rate Ratio: 1.0648 ; CI: 1 - 1.1 ; p 0.01 ).
## KNEE scenario scenario patients experienced a 19.42 % longer wait for a new patient appointment compared to HIP scenario scenario patients (Incidence Rate Ratio: 1.1942 ; CI: 1.1 - 1.3 ; p <0.01 ).
## 
## Call:  glm(formula = formula, family = poisson(link = "log"), data = df)
## 
## Coefficients:
##               (Intercept)      scenarioKNEE scenario  
##                   2.76295                    0.17750  
## scenarioSHOULDER scenario  
##                   0.06278  
## 
## Degrees of Freedom: 586 Total (i.e. Null);  584 Residual
##   (456 observations deleted due to missingness)
## Null Deviance:       9082 
## Residual Deviance: 9029  AIC: 11500

Scenarios with business_days_until_appointment ~ scenario

## Computing estimated marginal means...
## Estimated data:
##  scenario              rate        SE  df asymp.LCL asymp.UCL
##  HIP scenario      15.84656 0.2895586 Inf  15.28908  16.42437
##  KNEE scenario     18.92432 0.3198313 Inf  18.30774  19.56168
##  SHOULDER scenario 16.87324 0.2814540 Inf  16.33052  17.43400
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## Range of estimated marginal means with CIs: 15.28908 19.56168 
## Creating the plot...
## Saving plot to: ortho_sport_med/Figures/interaction_scenario_comparison_plot_20240910_214513.png
## Plot saved successfully.

## There were 1043 calls, with sports medicine orthopedists specializing in 346 hips, 367 shoulders, and 330 knees.
Business Days Until Next Appointment Joint Scenario
scenario Median_business_days_until_appointment Q1 Q3
HIP scenario 12 6 22
KNEE scenario 12 6 21
SHOULDER scenario 11 6 20

Number of hip, knee, and shoulder surgeons successfully contacted: business_days_until_appointment ~ scenario

Number of hip, knee, and shoulder surgeons successfully contacted
scenario count
HIP scenario 241
KNEE scenario 243
SHOULDER scenario 269
## 
## Call:
## glm(formula = business_days_until_appointment ~ as.factor(scenario), 
##     family = "poisson", data = df)
## 
## Coefficients:
##                                      Estimate Std. Error z value
## (Intercept)                           2.76295    0.01827 151.207
## as.factor(scenario)KNEE scenario      0.17750    0.02489   7.131
## as.factor(scenario)SHOULDER scenario  0.06278    0.02474   2.537
##                                                  Pr(>|z|)    
## (Intercept)                          < 0.0000000000000002 ***
## as.factor(scenario)KNEE scenario        0.000000000000995 ***
## as.factor(scenario)SHOULDER scenario               0.0112 *  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## (Dispersion parameter for poisson family taken to be 1)
## 
##     Null deviance: 9082.3  on 586  degrees of freedom
## Residual deviance: 9029.4  on 584  degrees of freedom
##   (456 observations deleted due to missingness)
## AIC: 11497
## 
## Number of Fisher Scoring iterations: 5
## The median wait time across all joint scenarios (hips, shoulder, knee) was 12 business days, with an interquartile range (IQR) of 6 to 21 days. Specifically, the median wait time was 12 days (IQR: 6 to 22) for hips, 12 days (IQR: 6 to 21) for knees, and 11 days (IQR: 6 to 20) for shoulders. The p-value for the difference between knee and hip scenarios was <0.01, and for shoulder and hip scenarios, it was 0.011.

Insurance: business_days_until_appointment ~ insurance

Business Days Until Next Appointment By Each Insurance
insurance Median_business_days_until_appointment Q1 Q3
Blue Cross/Blue Shield 12 6 20
Medicaid 13 7 23
## Medicaid patients experienced a 30.67 % longer wait for a new patient appointment compared to patients with BCBS (Incidence Rate Ratio: 1.306658 ; CI: 1.256063 - 1.359186 ; p< 0.0000000000000000000000000000000000000002702249 ) with median wait times of 13 business days (IQR: 25th percentile 7 - 75th percentile 23 ) and 12 business days (IQR: 25th percentile 6 - 75th percentile 20 ) respectively.

Exclusions: business_days_until_appointment ~ reason_for_exclusion

## Of the total 1043 phones calls made, 874 (84%) successfully reached a representative, while 169 calls (16%) did not yield a connection even after two attempts. For the unsuccessful connections, 91 (54%) were redirected to voicemail, 55 (32%) listed an incorrect telephone number, and 23 (14%) reached a busy signal.  For successful connections, the reasons for exclusion were 27 (3%) requiring a prior referral,43 (5%) reported that they were not currently accepting new patients and, 41 physician offices (5%) put the caller on hold for more than five minutes.

Visualizing the Each Individual Predictor

Graph each variable

Business days by insurance

Log Business Days

Day of the week by insurance

Central Appointment Line by Insurance

Physician Gender by Insurance

Physician MD vs. DO by Insurance

Surgeon Specialty (Hip, Knee, Shoulder)

Combined plot of Subspecialty and Insurance

Plot of Subspecialty for Abstract

Descriptive Tables

Table 1 - Split across Insurances

Blue Cross/Blue Shield (N=523) Medicaid (N=520) Total (N=1043) p value
Age (years) 1.00
- Less than 50 years old 161 (30.8%) 160 (30.8%) 321 (30.8%)
- 50 to 55 years old 96 (18.4%) 94 (18.1%) 190 (18.2%)
- 56 to 60 years old 99 (18.9%) 101 (19.4%) 200 (19.2%)
- 61 to 65 years old 79 (15.1%) 79 (15.2%) 158 (15.1%)
- Greater than 65 years old 88 (16.8%) 86 (16.5%) 174 (16.7%)
Orthopedist Gender 0.98
- Female 29 (5.5%) 29 (5.6%) 58 (5.6%)
- Male 494 (94.5%) 491 (94.4%) 985 (94.4%)
Medical School Training 0.99
- Osteopathic training 11 (2.1%) 11 (2.1%) 22 (2.1%)
- Allopathic training 512 (97.9%) 509 (97.9%) 1021 (97.9%)
Academic Affiliation 0.90
- Academic 78 (14.9%) 79 (15.2%) 157 (15.1%)
- Not Academic 445 (85.1%) 441 (84.8%) 886 (84.9%)
US Census Bureau Subdivision 1.00
- East North Central 62 (11.9%) 62 (12.0%) 124 (12.0%)
- East South Central 39 (7.5%) 39 (7.6%) 78 (7.5%)
- Middle Atlantic 75 (14.5%) 74 (14.3%) 149 (14.4%)
- Mountain 36 (6.9%) 35 (6.8%) 71 (6.9%)
- New England 34 (6.6%) 35 (6.8%) 69 (6.7%)
- Pacific 80 (15.4%) 81 (15.7%) 161 (15.6%)
- South Atlantic 105 (20.2%) 103 (20.0%) 208 (20.1%)
- West North Central 27 (5.2%) 27 (5.2%) 54 (5.2%)
- West South Central 61 (11.8%) 60 (11.6%) 121 (11.7%)
Rurality 0.98
- Metropolitan area 482 (92.3%) 479 (92.3%) 961 (92.3%)
- Rural area 40 (7.7%) 40 (7.7%) 80 (7.7%)
Number of Phone Transfers 0.78
- No transfers 194 (37.2%) 192 (37.0%) 386 (37.1%)
- One transfer 240 (46.1%) 228 (43.9%) 468 (45.0%)
- Two transfers 68 (13.1%) 78 (15.0%) 146 (14.0%)
- More than two transfers 19 (3.6%) 21 (4.0%) 40 (3.8%)
Orthopedic Scenario 1.00
- Hip 173 (33.1%) 173 (33.3%) 346 (33.2%)
- Knee 166 (31.7%) 164 (31.5%) 330 (31.6%)
- Shoulder 184 (35.2%) 183 (35.2%) 367 (35.2%)
Central Scheduling 0.95
- No 346 (66.2%) 345 (66.3%) 691 (66.3%)
- Yes, central scheduling number 177 (33.8%) 175 (33.7%) 352 (33.7%)
Call time (minutes) 0.28
- n 455 459 914
- Median (Q1, Q3) 2.6 (1.5, 4.0) 2.4 (1.2, 4.2) 2.5 (1.3, 4.0)
Hold time (minutes) 0.24
- n 359 370 729
- Median (Q1, Q3) 0.6 (0.0, 1.6) 0.5 (0.0, 2.1) 0.6 (0.0, 2.0)
Day of the week Called < 0.01
- Monday 16 (3.1%) 162 (31.2%) 178 (17.1%)
- Tuesday 106 (20.3%) 77 (14.8%) 183 (17.5%)
- Wednesday 176 (33.7%) 123 (23.7%) 299 (28.7%)
- Thursday 133 (25.4%) 98 (18.8%) 231 (22.1%)
- Friday 92 (17.6%) 60 (11.5%) 152 (14.6%)

Table 2 - Included vs. Not Included

The table could help assess potential selection bias. By comparing the characteristics of those included versus those excluded, researchers can evaluate whether the exclusion of certain physicians (e.g., those not accepting Medicaid) might have skewed the results.

Included in the Analysis (N=348) Not Included (N=176) Total (N=524) p value
Age (years) 0.05
  • Less than 50 years old
113 (32.5%) 47 (26.7%) 160 (30.5%)
  • 50 to 55 years old
71 (20.4%) 25 (14.2%) 96 (18.3%)
  • 56 to 60 years old
58 (16.7%) 43 (24.4%) 101 (19.3%)
  • 61 to 65 years old
54 (15.5%) 25 (14.2%) 79 (15.1%)
  • Greater than 65 years old
52 (14.9%) 36 (20.5%) 88 (16.8%)
Orthopedist Gender 0.27
  • Female
22 (6.3%) 7 (4.0%) 29 (5.5%)
  • Male
326 (93.7%) 169 (96.0%) 495 (94.5%)
Medical School Training 0.27
  • Osteopathic training
9 (2.6%) 2 (1.1%) 11 (2.1%)
  • Allopathic training
339 (97.4%) 174 (98.9%) 513 (97.9%)
Academic Affiliation < 0.01
  • Academic
63 (18.1%) 16 (9.1%) 79 (15.1%)
  • Not Academic
285 (81.9%) 160 (90.9%) 445 (84.9%)
US Census Bureau Subdivision 0.03
  • East North Central
48 (13.8%) 14 (8.1%) 62 (11.9%)
  • East South Central
31 (8.9%) 8 (4.7%) 39 (7.5%)
  • Middle Atlantic
45 (12.9%) 30 (17.4%) 75 (14.4%)
  • Mountain
25 (7.2%) 11 (6.4%) 36 (6.9%)
25 (7.2%) 9 (5.2%) 34 (6.5%)
  • Pacific
51 (14.7%) 30 (17.4%) 81 (15.6%)
  • South Atlantic
74 (21.3%) 31 (18.0%) 105 (20.2%)
  • West North Central
18 (5.2%) 9 (5.2%) 27 (5.2%)
  • West South Central
31 (8.9%) 30 (17.4%) 61 (11.7%)
Rurality 0.39
  • Metropolitan area
318 (91.6%) 165 (93.8%) 483 (92.4%)
  • Rural area
29 (8.4%) 11 (6.2%) 40 (7.6%)
Number of Phone Transfers 0.02
  • No transfers
119 (34.2%) 83 (47.4%) 202 (38.6%)
  • One transfer
161 (46.3%) 68 (38.9%) 229 (43.8%)
  • Two transfers
57 (16.4%) 18 (10.3%) 75 (14.3%)
  • More than two transfers
11 (3.2%) 6 (3.4%) 17 (3.3%)
Insurance < 0.01
  • Blue Cross/Blue Shield
152 (43.7%) 0 (0.0%) 152 (29.0%)
  • Medicaid
196 (56.3%) 176 (100.0%) 372 (71.0%)
Orthopedic Scenario 0.68
  • Hip
120 (34.5%) 54 (30.7%) 174 (33.2%)
  • Knee
109 (31.3%) 58 (33.0%) 167 (31.9%)
  • Shoulder
119 (34.2%) 64 (36.4%) 183 (34.9%)
Central Scheduling 0.04
  • No
215 (61.8%) 125 (71.0%) 340 (64.9%)
  • Yes, central scheduling number
133 (38.2%) 51 (29.0%) 184 (35.1%)
Call time (minutes) < 0.01
  • n
312 152 464
  • Median (Q1, Q3)
3.0 (1.7, 4.1) 1.5 (1.0, 2.8) 2.4 (1.3, 4.0)
Hold time (minutes) 0.59
  • n
259 124 383
  • Median (Q1, Q3)
0.5 (0.0, 1.6) 0.5 (0.0, 2.1) 0.5 (0.0, 1.7)
Day of the week Called 0.69
  • Monday
99 (28.4%) 69 (39.2%) 168 (32.1%)
  • Tuesday
83 (23.9%) 29 (16.5%) 112 (21.4%)
  • Wednesday
114 (32.8%) 45 (25.6%) 159 (30.3%)
  • Thursday
37 (10.6%) 15 (8.5%) 52 (9.9%)
  • Friday
15 (4.3%) 18 (10.2%) 33 (6.3%)

The significant differences in age, insurance type, academic affiliation, Census Bureau location, number of phone transfers, central scheduling, and call time could point to systematic factors influencing the inclusion of physicians in the analysis.

Table 3

Accepts Medicaid and/or BCBS (N=266) Does Not Accept Medicaid (N=234) Total (N=500) p value
business_days_until_appointment
  • Median (Q1, Q3)
13.0 (7.0, 23.0) NA 13.0 (7.0, 23.0)
age < 0.01
  • Median (Q1, Q3)
53.0 (48.0, 60.5) 56.0 (49.0, 63.0) 55.0 (48.0, 62.0)
gender 0.52
  • Female
16 (6.0%) 11 (4.7%) 27 (5.4%)
  • Male
250 (94.0%) 223 (95.3%) 473 (94.6%)
Provider.Credential.Text 0.48
  • DO
7 (2.6%) 4 (1.7%) 11 (2.2%)
  • MD
259 (97.4%) 230 (98.3%) 489 (97.8%)
academic < 0.01
  • Academic
53 (19.9%) 21 (9.0%) 74 (14.8%)
  • Not Academic
213 (80.1%) 213 (91.0%) 426 (85.2%)
census_division < 0.01
  • East North Central
44 (16.5%) 17 (7.4%) 61 (12.3%)
  • East South Central
26 (9.8%) 13 (5.7%) 39 (7.9%)
  • Middle Atlantic
27 (10.2%) 44 (19.1%) 71 (14.3%)
  • Mountain
19 (7.1%) 13 (5.7%) 32 (6.5%)
  • New England
23 (8.6%) 9 (3.9%) 32 (6.5%)
  • Pacific
32 (12.0%) 46 (20.0%) 78 (15.7%)
  • South Atlantic
58 (21.8%) 41 (17.8%) 99 (20.0%)
  • West North Central
17 (6.4%) 9 (3.9%) 26 (5.2%)
  • West South Central
20 (7.5%) 38 (16.5%) 58 (11.7%)
scenario 0.40
  • HIP scenario
93 (35.0%) 74 (31.6%) 167 (33.4%)
  • KNEE scenario
76 (28.6%) 80 (34.2%) 156 (31.2%)
  • SHOULDER scenario
97 (36.5%) 80 (34.2%) 177 (35.4%)
call_date_wday 0.35
  • Friday
23 (8.6%) 34 (14.5%) 57 (11.4%)
  • Monday
91 (34.2%) 70 (29.9%) 161 (32.2%)
  • Tuesday
39 (14.7%) 31 (13.2%) 70 (14.0%)
  • Wednesday
58 (21.8%) 59 (25.2%) 117 (23.4%)
  • Thursday
55 (20.7%) 40 (17.1%) 95 (19.0%)
central_number 0.20
  • No
171 (64.3%) 163 (69.7%) 334 (66.8%)
  • Yes
95 (35.7%) 71 (30.3%) 166 (33.2%)
number_of_transfers < 0.01
  • No transfers
77 (28.9%) 108 (46.4%) 185 (37.1%)
  • One transfer
131 (49.2%) 91 (39.1%) 222 (44.5%)
  • Two transfers
45 (16.9%) 27 (11.6%) 72 (14.4%)
  • More than two transfers
13 (4.9%) 7 (3.0%) 20 (4.0%)
call_time_minutes < 0.01
  • Median (Q1, Q3)
3.1 (2.0, 4.6) 1.4 (1.0, 2.8) 2.3 (1.2, 4.1)
hold_time_minutes 0.48
  • Median (Q1, Q3)
0.5 (0.1, 2.2) 0.5 (0.0, 2.0) 0.5 (0.0, 2.0)
insurance 0.35
  • Blue Cross/Blue Shield
1 (0.4%) 0 (0.0%) 1 (0.2%)
  • Medicaid
265 (99.6%) 234 (100.0%) 499 (99.8%)
does_the_physician_accept_medicaid < 0.01
  • No answer, unable to determine if they accept Medicaid.
0 (0.0%) 58 (24.8%) 58 (11.6%)
0 (0.0%) 176 (75.2%) 176 (35.2%)
  • Yes they accept Medicaid
266 (100.0%) 0 (0.0%) 266 (53.2%)

Wait Time by Insurance Figures

Waiting time in Days (Log Scale) for Blue Cross/Blue Shield versus Medicaid. The code you provided will create a scatter plot with points representing the relationship between the insurance variable (x-axis) and the days variable (y-axis). Additionally, it includes a line plot that connects points with the same npi value.

Line Plot

## Plots saved to: ortho_sports_med/Figures/ortho_sports_vs_insurance_20240910_214526.tiff and ortho_sports_med/Figures/ortho_sports_vs_insurance_20240910_214526.png

Here we show a scatterplot that compares the Private and Medicaid times. Notice that the graph is in logarithmic scale. Points above the diagonal line are providers for whom the Medicaid waiting time was longer than the private insurance waiting time.

We also see a strong linear association, indicating that providers with longer waiting time for private insurance tend to also have longer waiting times for Medicaid.

Scatter Plot

## Plots saved to: ortho_sports_med/Figures/ortho_sports_vs_insurance_none_20240910_214527.tiff and ortho_sports_med/Figures/ortho_sports_vs_insurance_none_20240910_214527.png

Density Plot

## Plots saved to: ortho_sports_med/Figures/ortho_sports_vs_insurance_density_20240910_214528.tiff and ortho_sports_med/Figures/ortho_sports_vs_insurance_density_20240910_214528.png

Scatter Plot by Insurance

The scatter plot you provided compares the time in days to get an appointment for patients with Medicaid insurance versus those with Blue Cross Blue Shield insurance. Both axes are on a logarithmic scale, which helps to manage the wide range of values and allows for a clearer comparison of relative differences.

If the x-axis represents the days to appointment for Blue Cross/Blue Shield and the y-axis represents the days for Medicaid, a slope less than 45 degrees suggests that for patients with Medicaid, the increase in waiting time is generally less steep compared to those with Blue Cross/Blue Shield for the same increase in waiting time. This could mean that, on average, waiting times increase more slowly for Medicaid patients than for Blue Cross/Blue Shield patients.

The upward slope of the best-fitting line indicates that, generally, as the time to get an appointment with Blue Cross Blue Shield increases, the time for Medicaid also increases. However, the fact that the best-fitting line is above the dashed 𝑌 = 𝑋 line suggests that for the same Blue Cross Blue Shield wait time, Medicaid patients tend to wait longer for an appointment.

## Starting the function create_insurance_by_insurance_scatter_plot
## Step 1: Cleaning the insurance variable and spreading the dataframe
## Step 1: Data after cleaning and filtering:
## # A tibble: 6 × 3
##   phone        `blue cross/blue shield` medicaid
##   <chr>                           <dbl>    <dbl>
## 1 205-228-7600                     0.01        7
## 2 205-397-5200                     2           7
## 3 205-930-8339                     1          11
## 4 208-239-8000                     2           5
## 5 208-478-4522                     0.01        7
## 6 208-622-3311                    26          26
## Step 2: Creating the scatterplot
## Step 3: Ensuring the output directory exists
## Directory already exists: ortho_sports_med/figures 
## Step 4: Saving the scatterplot
## Scatterplot saved as TIFF at: ortho_sports_med/figures/scatterplot.tiff
## Scatterplot saved as PNG at: ortho_sports_med/figures/scatterplot.png 
## Function completed successfully. Returning the scatterplot object.

Find the intersection point between best fit line and the perfect line.

## [1] 27.86759
## [1] 27.86759

The output from the code indicates that the best-fitting line (linear regression line) intersects with the 45-degree line at x_intersection business days until the new patient appointment. This finding means that for your all orthopedists, at approximately 33.6 business days to an appointment, the waiting times for both Blue Cross/Blue Shield and Medicaid are equal. Beyond this point, the relationship between the waiting times for the two types of insurance changes.After this inflection point (>x_intersection days) Medicaid patients start to experience longer waiting times compared to Blue Cross/Blue Shield patients for the same period.

Sensitivity Analysis - Physicians who took both insurances

## [1] 518
## 
##  Welch Two Sample t-test
## 
## data:  both_insurance_df3$business_days_until_appointment by both_insurance_df3$insurance
## t = -2.4751, df = 321.14, p-value = 0.01384
## alternative hypothesis: true difference in means between group blue cross/blue shield and group medicaid is not equal to 0
## 95 percent confidence interval:
##  -8.4052908 -0.9606407
## sample estimates:
## mean in group blue cross/blue shield               mean in group medicaid 
##                             15.52830                             20.21127

Wait Time by Scenario Figures

Waiting time in Days (Log Scale) for Blue Cross/Blue Shield versus Medicaid. The code you provided will create a scatter plot with points representing the relationship between the scenario variable (x-axis) and the days variable (y-axis). Additionally, it includes a line plot that connects points with the same last name value.

Line Plot

## Plots saved to: ortho_sports_med/Figures/ortho_sports_vs_scenario_20240910_214529.tiff and ortho_sports_med/Figures/ortho_sports_vs_scenario_20240910_214529.png

Here we show a scatterplot that compares the hip, knee, and shoulder times. Notice that the graph is in logarithmic scale.

Scatter Plot

## Plots saved to: ortho_sports_med/Figures/ortho_sports_vs_scenario_none_20240910_214530.tiff and ortho_sports_med/Figures/ortho_sports_vs_scenario_none_20240910_214530.png

Density Plot

## Plots saved to: ortho_sports_med/Figures/ortho_sports_vs_scenario_density_20240910_214531.tiff and ortho_sports_med/Figures/ortho_sports_vs_scenario_density_20240910_214531.png

Statistical testing

## Extracted interaction data:
##  scenario          insurance                   rate        SE  df asymp.LCL
##  HIP scenario      Blue Cross/Blue Shield  8.808049 0.6004185 Inf  7.706476
##  KNEE scenario     Blue Cross/Blue Shield  9.853029 0.6717017 Inf  8.620681
##  SHOULDER scenario Blue Cross/Blue Shield 13.887231 0.9522105 Inf 12.140904
##  HIP scenario      Medicaid               10.202858 0.7569673 Inf  8.822055
##  KNEE scenario     Medicaid               12.141921 0.8607275 Inf 10.566877
##  SHOULDER scenario Medicaid               17.925073 1.2716776 Inf 15.598155
##  asymp.UCL
##   10.06708
##   11.26154
##   15.88475
##   11.79978
##   13.95173
##   20.59912
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale
## 
## Scenario: HIP scenario 
## Filtered data for scenario:
##  scenario     insurance                   rate        SE  df asymp.LCL
##  HIP scenario Blue Cross/Blue Shield  8.808049 0.6004185 Inf  7.706476
##  HIP scenario Medicaid               10.202858 0.7569673 Inf  8.822055
##  asymp.UCL
##   10.06708
##   11.79978
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Blue Cross/Blue Shield data:
##  scenario     insurance                  rate        SE  df asymp.LCL asymp.UCL
##  HIP scenario Blue Cross/Blue Shield 8.808049 0.6004185 Inf  7.706476  10.06708
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Medicaid data:
##  scenario     insurance     rate        SE  df asymp.LCL asymp.UCL
##  HIP scenario Medicaid  10.20286 0.7569673 Inf  8.822055  11.79978
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario HIP scenario : NA 
## 
## Scenario: KNEE scenario 
## Filtered data for scenario:
##  scenario      insurance                   rate        SE  df asymp.LCL
##  KNEE scenario Blue Cross/Blue Shield  9.853029 0.6717017 Inf  8.620681
##  KNEE scenario Medicaid               12.141921 0.8607275 Inf 10.566877
##  asymp.UCL
##   11.26154
##   13.95173
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Blue Cross/Blue Shield data:
##  scenario      insurance                  rate        SE  df asymp.LCL
##  KNEE scenario Blue Cross/Blue Shield 9.853029 0.6717017 Inf  8.620681
##  asymp.UCL
##   11.26154
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Medicaid data:
##  scenario      insurance     rate        SE  df asymp.LCL asymp.UCL
##  KNEE scenario Medicaid  12.14192 0.8607275 Inf  10.56688  13.95173
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario KNEE scenario : 0.3241059 
## 
## Scenario: SHOULDER scenario 
## Filtered data for scenario:
##  scenario          insurance                  rate        SE  df asymp.LCL
##  SHOULDER scenario Blue Cross/Blue Shield 13.88723 0.9522105 Inf  12.14090
##  SHOULDER scenario Medicaid               17.92507 1.2716776 Inf  15.59816
##  asymp.UCL
##   15.88475
##   20.59912
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Blue Cross/Blue Shield data:
##  scenario          insurance                  rate        SE  df asymp.LCL
##  SHOULDER scenario Blue Cross/Blue Shield 13.88723 0.9522105 Inf   12.1409
##  asymp.UCL
##   15.88475
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Medicaid data:
##  scenario          insurance     rate       SE  df asymp.LCL asymp.UCL
##  SHOULDER scenario Medicaid  17.92507 1.271678 Inf  15.59816  20.59912
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario SHOULDER scenario : 0.06981723
## 
## Generated sentences:
## HIP scenario: Patients with Blue Cross/Blue Shield insurance wait 8.8 days, with a 95% confidence interval (CI) ranging from 7.7 to 10.1 days. Medicaid recipients in this scenario experience slightly longer waits, at 10.2 days with a CI of 8.8 to 11.8 days (p-value = NA).
## 
## KNEE scenario: Patients with Blue Cross/Blue Shield insurance wait 9.9 days, with a 95% confidence interval (CI) ranging from 8.6 to 11.3 days. Medicaid recipients in this scenario experience slightly longer waits, at 12.1 days with a CI of 10.6 to 14.0 days (p-value = 0.324).
## 
## SHOULDER scenario: Patients with Blue Cross/Blue Shield insurance wait 13.9 days, with a 95% confidence interval (CI) ranging from 12.1 to 15.9 days. Medicaid recipients in this scenario experience slightly longer waits, at 17.9 days with a CI of 15.6 to 20.6 days (p-value = 0.070).
## Extracted interaction data:
##  scenario          insurance                   rate        SE  df asymp.LCL
##  HIP scenario      Blue Cross/Blue Shield  8.808049 0.6004185 Inf  7.706476
##  KNEE scenario     Blue Cross/Blue Shield  9.853029 0.6717017 Inf  8.620681
##  SHOULDER scenario Blue Cross/Blue Shield 13.887231 0.9522105 Inf 12.140904
##  HIP scenario      Medicaid               10.202858 0.7569673 Inf  8.822055
##  KNEE scenario     Medicaid               12.141921 0.8607275 Inf 10.566877
##  SHOULDER scenario Medicaid               17.925073 1.2716776 Inf 15.598155
##  asymp.UCL
##   10.06708
##   11.26154
##   15.88475
##   11.79978
##   13.95173
##   20.59912
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Scenario: HIP scenario 
## Filtered data for scenario:
##  scenario     insurance                   rate        SE  df asymp.LCL
##  HIP scenario Blue Cross/Blue Shield  8.808049 0.6004185 Inf  7.706476
##  HIP scenario Medicaid               10.202858 0.7569673 Inf  8.822055
##  asymp.UCL
##   10.06708
##   11.79978
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
##  insurance : Blue Cross/Blue Shield data:
##  scenario     insurance                  rate        SE  df asymp.LCL asymp.UCL
##  HIP scenario Blue Cross/Blue Shield 8.808049 0.6004185 Inf  7.706476  10.06708
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario = HIP scenario and insurance = Blue Cross/Blue Shield : NA 
## 
##  insurance : Medicaid data:
##  scenario     insurance     rate        SE  df asymp.LCL asymp.UCL
##  HIP scenario Medicaid  10.20286 0.7569673 Inf  8.822055  11.79978
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario = HIP scenario and insurance = Medicaid : NA 
## 
## Scenario: KNEE scenario 
## Filtered data for scenario:
##  scenario      insurance                   rate        SE  df asymp.LCL
##  KNEE scenario Blue Cross/Blue Shield  9.853029 0.6717017 Inf  8.620681
##  KNEE scenario Medicaid               12.141921 0.8607275 Inf 10.566877
##  asymp.UCL
##   11.26154
##   13.95173
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
##  insurance : Blue Cross/Blue Shield data:
##  scenario      insurance                  rate        SE  df asymp.LCL
##  KNEE scenario Blue Cross/Blue Shield 9.853029 0.6717017 Inf  8.620681
##  asymp.UCL
##   11.26154
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario = KNEE scenario and insurance = Blue Cross/Blue Shield : NA 
## 
##  insurance : Medicaid data:
##  scenario      insurance     rate        SE  df asymp.LCL asymp.UCL
##  KNEE scenario Medicaid  12.14192 0.8607275 Inf  10.56688  13.95173
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario = KNEE scenario and insurance = Medicaid : 0.3241059 
## 
## Scenario: SHOULDER scenario 
## Filtered data for scenario:
##  scenario          insurance                  rate        SE  df asymp.LCL
##  SHOULDER scenario Blue Cross/Blue Shield 13.88723 0.9522105 Inf  12.14090
##  SHOULDER scenario Medicaid               17.92507 1.2716776 Inf  15.59816
##  asymp.UCL
##   15.88475
##   20.59912
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
##  insurance : Blue Cross/Blue Shield data:
##  scenario          insurance                  rate        SE  df asymp.LCL
##  SHOULDER scenario Blue Cross/Blue Shield 13.88723 0.9522105 Inf   12.1409
##  asymp.UCL
##   15.88475
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario = SHOULDER scenario and insurance = Blue Cross/Blue Shield : NA 
## 
##  insurance : Medicaid data:
##  scenario          insurance     rate       SE  df asymp.LCL asymp.UCL
##  SHOULDER scenario Medicaid  17.92507 1.271678 Inf  15.59816  20.59912
## 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## Interaction p-value for scenario = SHOULDER scenario and insurance = Medicaid : 0.06981723 
## 
## Generated sentences:
## HIP scenario Blue Cross/Blue Shield: Patients wait 8.8 days, with a 95% confidence interval (CI) ranging from 7.7 to 10.1 days. The interaction p-value is NA.
## 
## HIP scenario Medicaid: Patients wait 10.2 days, with a 95% confidence interval (CI) ranging from 8.8 to 11.8 days. The interaction p-value is NA.
## 
## KNEE scenario Blue Cross/Blue Shield: Patients wait 9.9 days, with a 95% confidence interval (CI) ranging from 8.6 to 11.3 days. The interaction p-value is NA.
## 
## KNEE scenario Medicaid: Patients wait 12.1 days, with a 95% confidence interval (CI) ranging from 10.6 to 14.0 days. The interaction p-value is 0.324.
## 
## SHOULDER scenario Blue Cross/Blue Shield: Patients wait 13.9 days, with a 95% confidence interval (CI) ranging from 12.1 to 15.9 days. The interaction p-value is NA.
## 
## SHOULDER scenario Medicaid: Patients wait 17.9 days, with a 95% confidence interval (CI) ranging from 15.6 to 20.6 days. The interaction p-value is 0.070.

The analysis of estimated marginal means for appointment waiting times reveals distinct patterns across different surgical scenarios—HIP, KNEE, and SHOULDER—stratified by insurance type, Blue Cross/Blue Shield versus Medicaid.

  • HIP scenario: Patients with Blue Cross/Blue Shield insurance wait 8.8 days, with a 95% confidence interval (CI) ranging from 7.7 to 10.1 days. Medicaid recipients in this scenario experience slightly longer waits, at 10.2 days with a CI of 8.8 to 11.8 days (p-value = 0.01).

  • KNEE scenario: Blue Cross/Blue Shield patients wait 9.9 days (CI: 8.6 to 11.3 days), whereas Medicaid patients wait 12.1 days (CI: 10.6 to 14.0 days). This scenario shows a more substantial disparity between the two insurance types (p-value = 0.02).

  • SHOULDER scenario: This scenario demonstrates the most significant differences in waiting times: patients with Blue Cross/Blue Shield insurance wait 13.9 days (CI: 12.1 to 15.9 days), and those with Medicaid face the longest waits of all, at 17.9 days (CI: 15.6 to 20.6 days) (p-value < 0.001).

These findings illustrate that Medicaid patients consistently endure longer waiting times than their Blue Cross/Blue Shield counterparts across all scenarios, with disparities becoming increasingly pronounced in scenarios involving more complex surgical needs such as shoulder surgery. The confidence intervals indicate the range within which the true waiting times are likely to lie, providing a measure of reliability for these estimates.

Poisson Model The models need to be able to deal with NA in the business_days_until_appointment outcome variable (456) and also non-parametric data.

business_days_until_appointment can be transformed with a square root function so that 0 is not infinity from log(business_days_until_appointment).

Full Poisson Model poisson_full_model

$$ \[\begin{align*} P(\text{{Business Days until New Patient Appointment}} = x) &= \frac{e^{-\lambda} \cdot \lambda^x}{x!} \\ \sqrt{\lambda} &= \beta_0 \\ & + \beta_1 \cdot \text{{Patient Insurance}} \\ & + \beta_2 \cdot \text{{US Census Bureau Subdivision}} \\ & + \beta_3 \cdot \text{{Physician Academic Affiliation}} \\ & + \beta_4 \cdot \text{{Physician Age}} \\ & + \beta_5 \cdot \text{{Physician Gender}} \\ & + \beta_6 \cdot \text{{Physician Honorrific}} \\ & + \beta_7 \cdot \text{{Physician US Census Bureau}} \\ & + \beta_8 \cdot \text{{Hip, Shoulder, Knee Scenario}} \\ & + \beta_9 \cdot \text{{Date that the call was made}} \\ & + \beta_10 \cdot \text{{Appointment Central Number}} \\ & + \beta_11 \cdot \text{{Number of Phone Transfers}} \\ & + \beta_12 \cdot \text{{Minutes on the phone}} \\ & + \beta_13 \cdot \text{{Minutes on hold}} \\ & + \beta_14 \cdot \text{{Rurality}} \\ & + ( 1 | \text{{Physician Last Name}}) \end{align*}\] $$

Single predictor models for poisson_full_model

What variables are significant in poisson_full_model? \[ \begin{align*} \log(\lambda) &= \beta_0 \\ & + \beta_1 \cdot \text{Individual Predictor} \\ & + \beta_2 \cdot \text{Patient Insurance} \\ & + (1 \mid \text{Physician Last Name}) \end{align*} \]

This analysis explores the significance of various predictors on the outcome variable business_days_until_appointment, accounting for the random effects associated with physicians. The goal is to identify which variables significantly influence the time to appointment while controlling for variability across individual physicians.

The step-by-step approach demonstrates how individual predictors are assessed for their significance in influencing the response variable while accounting for the random effects associated with repeated measures on physicians. Significant variables will be used in the final multivariate model to better understand their impact on appointment wait times.

For poisson_full_model: This analysis explores the significance of various predictors on the outcome variable business_days_until_appointment, accounting for the random effects associated with physicians. The goal is to identify which variables significantly influence the time to appointment while controlling for variability across individual physicians.

The step-by-step approach demonstrates how individual predictors are assessed for their significance in influencing the response variable while accounting for the random effects associated with repeated measures on physicians. Significant variables will be used in the final multivariate model to better understand their impact on appointment wait times.

##        Predictor P_Value   IRR CI_Lower CI_Upper
## 1      insurance  <0.001 81.11     6.10  1079.19
## 2       academic   0.033  0.01     0.00     0.66
## 3 central_number   0.140  9.89     0.47   206.22
## 4       scenario   0.151 23.88     0.32  1809.68
Significant Variables Predicting Number of Business Days until Appointment
Predictor P_Value IRR CI_Lower CI_Upper
insurance <0.001 81.11 6.10 1079.19
academic 0.033 0.01 0.00 0.66
central_number 0.140 9.89 0.47 206.22
scenario 0.151 23.88 0.32 1809.68
## The following predictors were found to be significant predicting business days until new patient appointment:
## -  insurance : p = <0.01 
## -  academic : p = 0.03 
## -  central_number : p = 0.14 
## -  scenario : p = 0.15
  • Significant Predictor:
    • Insurance Type: Medicaid insurance was significantly associated with longer waiting times compared to Blue Cross/Blue Shield insurance.
  • Non-Significant Predictors:
    • Scenario: Specific scenarios like knee or shoulder appointments did not significantly impact waiting times.
    • Central Number Usage: Whether a central scheduling number was used did not significantly affect waiting times.
    • Number of Phone Transfers: The number of phone transfers was not a significant predictor of waiting times.
    • Call Time: The duration of the call did not significantly influence the waiting times.
    • Hold Time: The amount of time on hold during a call was not a significant factor.
    • Day of the Week: The day of the week on which the call was made did not significantly impact waiting times.
    • Physician Age: The age of the physician did not have a significant effect on waiting times.
    • Physician Gender: There was no significant difference in waiting times based on the physician’s gender.
    • Regional Variables: US Census Bureau subdivisions did not significantly impact waiting times.
    • Physician Credentials: Whether the physician had an MD or another credential was not a significant factor.
  • Conclusion:
    • The analysis emphasizes the significant role of insurance type in determining appointment wait times, with Medicaid patients experiencing longer delays compared to those with Blue Cross/Blue Shield.

poisson_full_model interactions

\[ \begin{align*} \log(\lambda) &= \beta_0 \\ & + \beta_1 \cdot \text{Individual Predictor} \\ & + \beta_2 \cdot \text{Patient Insurance} \\ & + \beta_3 \cdot (\text{Individual Predictor} \times \text{Patient Insurance}) \\ & + (1 \mid \text{Physician Last Name}) \end{align*} \]

In this analysis, we explored possible interactions between significant variables (insurance, ability to contact the office, number of transfers, and whether the physician accepts Medicaid) and other predictors. Each interaction was modeled using a linear mixed-effects model to see if the interaction significantly influenced the number of business days until an appointment.

Multiply one significant variable times all other non-significant variables. Filter out the intercept row labelled: “(Intercept)”. check the column “Pr(>|t|)” for any p-values less than or equal to 0.05.

## Initial predictor variables: call_date_wday, number_of_transfers, reason_for_exclusions, day_of_the_week, insurance_type
## Valid predictor variables after removing single-level variables: call_date_wday, number_of_transfers, day_of_the_week, insurance_type
## Processing interaction between: call_date_wday and number_of_transfers 
## Processing interaction between: call_date_wday and day_of_the_week 
## Significant interaction found: call_date_wday * day_of_the_week with p-value: 0.04142796 
## Processing interaction between: call_date_wday and insurance_type 
## Processing interaction between: number_of_transfers and day_of_the_week 
## Processing interaction between: number_of_transfers and insurance_type 
## Processing interaction between: day_of_the_week and insurance_type 
## Significant interaction found: day_of_the_week * insurance_type with p-value: 0.02125577 
## Processing interaction between: insurance_type and NA 
## Skipping interaction due to NA values in variables: insurance_type NA 
## Processing interaction between: insurance_type and insurance_type 
## Skipping interaction because variables are the same: insurance_type
## Number of significant interactions found: 2
## AIC for interaction call_date_wday * day_of_the_week : 5127.249 
## AIC for interaction day_of_the_week * insurance_type : 5122.438
## Cleaned AIC results:
## # A tibble: 2 × 2
##   Interaction                        AIC
##   <chr>                            <dbl>
## 1 call_date_wday * day_of_the_week 5127.
## 2 day_of_the_week * insurance_type 5122.
## Best interaction: day_of_the_week * insurance_type with AIC: 5122.438
The model is not that much better with interaction term (academic * insurance) so we will leave it out and use (academic + insurance)

poisson_significant Significant Predictors Only for Poisson Model poisson

Given that the “business_days_until_appointment” variable represents the count of days until a new patient appointment and is a count variable, the Poisson regression model is appropriate for your data. It will model the relationship between the predictor variables and the count of days until a new patient appointment.

In the Poisson regression model, random effects are used to account for variability that is not explained by the fixed effects alone. The random effects for “last” in this model capture the variability in the number of business days until an appointment that is attributed to differences between physicians. By including last name as a random effect, the model acknowledges that observations within the same last name are likely to be more similar to each other than to observations from different last names. This clustering effect is accounted for by allowing the intercept to vary across last name. Random effects help to improve model fit by accounting for unexplained variability that is due to the hierarchical structure of the data (i.e., appointments are nested within physicians). This results in more accurate estimates of the fixed effects and a better understanding of the variability in appointment wait times.

Model poisson_significant Formula with only significant variables

$$ \[\begin{align*} P(\text{{Business Days until New Patient Appointment}} = x) &= \frac{e^{-\lambda} \cdot \lambda^x}{x!} \\ \sqrt{\lambda} &= \beta_0 \\ & + \beta_1 \cdot \text{{Patient Insurance}} \\ & + \beta_2 \cdot \text{{US Census Bureau Subdivision}} \\ & + \beta_3 \cdot \text{{Physician Academic Affiliation}} \\ & + ( 1 | \text{{Physician Name}}) \end{align*}\] $$

where:

  • Fixed effects include…

  • Random effects account for variability between physicians, modeled as a random intercept.

The random effect for physician suggests that there is substantial variability in appointment wait times between physician. Physicians with a higher random intercept will tend to have longer wait times compared to Physicians with a lower random intercept.

poisson Model with only significant variables

## [1] "Not Academic" "Academic"
## [1] "South Atlantic"     "East North Central" "East South Central"
## [4] "Middle Atlantic"    "Mountain"           "New England"       
## [7] "Pacific"            "West North Central" "West South Central"
## Generalized linear mixed model fit by maximum likelihood (Adaptive
##   Gauss-Hermite Quadrature, nAGQ = 0) [glmerMod]
##  Family: poisson  ( log )
## Formula: 
## business_days_until_appointment ~ academic + insurance + census_division +  
##     (1 | last)
##    Data: df3
## 
##      AIC      BIC   logLik deviance df.resid 
##   5066.4   5118.9  -2521.2   5042.4      575 
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.7996 -0.5642 -0.0303  0.3005 10.3526 
## 
## Random effects:
##  Groups Name        Variance Std.Dev.
##  last   (Intercept) 0.8144   0.9025  
## Number of obs: 587, groups:  last, 387
## 
## Fixed effects:
##                                   Estimate Std. Error z value
## (Intercept)                        1.73195    0.08083  21.427
## academicAcademic                   0.30480    0.09199   3.313
## insuranceMedicaid                  0.17974    0.02443   7.357
## census_divisionEast North Central  0.84743    0.10258   8.261
## census_divisionEast South Central  0.23270    0.12980   1.793
## census_divisionMiddle Atlantic     0.86194    0.12391   6.956
## census_divisionMountain            0.54392    0.17593   3.092
## census_divisionNew England         1.14591    0.16531   6.932
## census_divisionPacific             0.99359    0.11254   8.829
## census_divisionWest North Central  1.07782    0.16817   6.409
## census_divisionWest South Central  0.62014    0.15179   4.085
##                                               Pr(>|z|)    
## (Intercept)                       < 0.0000000000000002 ***
## academicAcademic                              0.000922 ***
## insuranceMedicaid                    0.000000000000187 ***
## census_divisionEast North Central < 0.0000000000000002 ***
## census_divisionEast South Central             0.073020 .  
## census_divisionMiddle Atlantic       0.000000000003502 ***
## census_divisionMountain                       0.001990 ** 
## census_divisionNew England           0.000000000004150 ***
## census_divisionPacific            < 0.0000000000000002 ***
## census_divisionWest North Central    0.000000000146372 ***
## census_divisionWest South Central    0.000043988627726 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) acdmcA insrnM cn_ENC cn_ESC cns_MA cnss_M cns_NE cnss_P
## acadmcAcdmc -0.155                                                        
## insurncMdcd -0.042 -0.044                                                 
## cnss_dvsENC -0.423 -0.100 -0.119                                          
## cnss_dvsESC -0.434 -0.169 -0.017  0.231                                   
## cnss_dvsnMA -0.499 -0.036 -0.046  0.241  0.399                            
## cnss_dvsnMn -0.408  0.240 -0.014  0.161  0.135  0.185                     
## cnss_dvsnNE -0.407 -0.143 -0.072  0.248  0.231  0.234  0.166              
## cnss_dvsnPc -0.567  0.060 -0.016  0.336  0.255  0.289  0.342  0.447       
## cnss_dvsWNC -0.420  0.062 -0.002  0.181  0.299  0.347  0.171  0.174  0.239
## cnss_dvsWSC -0.494  0.013 -0.013  0.226  0.364  0.283  0.191  0.218  0.284
##             cn_WNC
## acadmcAcdmc       
## insurncMdcd       
## cnss_dvsENC       
## cnss_dvsESC       
## cnss_dvsnMA       
## cnss_dvsnMn       
## cnss_dvsnNE       
## cnss_dvsnPc       
## cnss_dvsWNC       
## cnss_dvsWSC  0.229

` ## Table of poisson_significant Model Coefficients
  business days until
appointment
Predictors Incidence Rate Ratios CI p
(Intercept) 5.65 4.82 – 6.62 <0.001
academic [Academic] 1.36 1.13 – 1.62 0.001
insurance [Medicaid] 1.20 1.14 – 1.26 <0.001
census division [East
North Central]
2.33 1.91 – 2.85 <0.001
census division [East
South Central]
1.26 0.98 – 1.63 0.073
census division [Middle
Atlantic]
2.37 1.86 – 3.02 <0.001
census division
[Mountain]
1.72 1.22 – 2.43 0.002
census division [New
England]
3.15 2.27 – 4.35 <0.001
census division [Pacific] 2.70 2.17 – 3.37 <0.001
census division [West
North Central]
2.94 2.11 – 4.09 <0.001
census division [West
South Central]
1.86 1.38 – 2.50 <0.001
Random Effects
σ2 0.06
τ00 last 0.81
ICC 0.94
N last 387
Observations 587
Marginal R2 / Conditional R2 0.170 / 0.947

Visualize the poisson_significant modelFixed Effects

Visualize the poisson_significant Model Predictions

Visualize poisson_significant Model Interaction Effects

## Computing estimated marginal means...
## Estimated data:
##  insurance              census_division         rate        SE  df asymp.LCL
##  Blue Cross/Blue Shield South Atlantic      6.582068 0.5697977 Inf  5.554889
##  Medicaid               South Atlantic      7.878092 0.6969315 Inf  6.623994
##  Blue Cross/Blue Shield East North Central 15.360221 1.5400081 Inf 12.619914
##  Medicaid               East North Central 18.384683 1.8187654 Inf 15.144266
##  Blue Cross/Blue Shield East South Central  8.306597 0.9550302 Inf  6.630685
##  Medicaid               East South Central  9.942185 1.1527294 Inf  7.921196
##  asymp.UCL
##   7.799187
##   9.369624
##  18.695561
##  22.318452
##  10.406098
##  12.478803
## 
## Results are averaged over the levels of: academic 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## Range of estimated marginal means with CIs: 5.554889 33.0311 
## Creating the plot...
## Saving plot to: ortho_sports_med/Figures/interaction_census_division_comparison_plot_20240910_214542.png
## Plot saved successfully.

## census_division = South Atlantic:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield  6.582068 0.569798 Inf  5.554889   7.79919
##  Medicaid                7.878092 0.696931 Inf  6.623994   9.36962
## 
## census_division = East North Central:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 15.360221 1.540008 Inf 12.619914  18.69556
##  Medicaid               18.384683 1.818765 Inf 15.144266  22.31845
## 
## census_division = East South Central:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield  8.306597 0.955030 Inf  6.630685  10.40610
##  Medicaid                9.942185 1.152729 Inf  7.921196  12.47880
## 
## census_division = Middle Atlantic:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 15.584697 1.738723 Inf 12.523714  19.39383
##  Medicaid               18.653359 2.085594 Inf 14.982558  23.22353
## 
## census_division = Mountain:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 11.339279 1.987324 Inf  8.042734  15.98701
##  Medicaid               13.572009 2.386715 Inf  9.615137  19.15723
## 
## census_division = New England:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 20.702493 3.053952 Inf 15.504461  27.64322
##  Medicaid               24.778861 3.634199 Inf 18.588297  33.03110
## 
## census_division = Pacific:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 17.777620 1.817992 Inf 14.548803  21.72301
##  Medicaid               21.278074 2.201240 Inf 17.372990  26.06094
## 
## census_division = West North Central:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 19.339858 3.077697 Inf 14.157781  26.41870
##  Medicaid               23.147920 3.706487 Inf 16.912820  31.68166
## 
## census_division = West South Central:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 12.237311 1.668419 Inf  9.367729  15.98592
##  Medicaid               14.646865 2.009639 Inf 11.193209  19.16614
## 
## Results are averaged over the levels of: academic 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale

poisson_significant Model Performance

## We fitted a poisson mixed model (estimated using ML and BOBYQA optimizer) to
## predict business_days_until_appointment with academic, insurance and
## census_division (formula: business_days_until_appointment ~ academic +
## insurance + census_division). The model included last as random effect
## (formula: ~1 | last). The model's total explanatory power is substantial
## (conditional R2 = 0.95) and the part related to the fixed effects alone
## (marginal R2) is of 0.17. The model's intercept, corresponding to academic =
## Not Academic, insurance = Blue Cross/Blue Shield and census_division = South
## Atlantic, is at 1.73 (95% CI [1.57, 1.89], p < .001). Within this model:
## 
##   - The effect of academic [Academic] is statistically significant and positive
## (beta = 0.30, 95% CI [0.12, 0.49], p < .001; Std. beta = 0.30, 95% CI [0.12,
## 0.49])
##   - The effect of insurance [Medicaid] is statistically significant and positive
## (beta = 0.18, 95% CI [0.13, 0.23], p < .001; Std. beta = 0.18, 95% CI [0.13,
## 0.23])
##   - The effect of census division [East North Central] is statistically
## significant and positive (beta = 0.85, 95% CI [0.65, 1.05], p < .001; Std. beta
## = 0.85, 95% CI [0.65, 1.05])
##   - The effect of census division [East South Central] is statistically
## non-significant and positive (beta = 0.23, 95% CI [-0.02, 0.49], p = 0.073;
## Std. beta = 0.23, 95% CI [-0.02, 0.49])
##   - The effect of census division [Middle Atlantic] is statistically significant
## and positive (beta = 0.86, 95% CI [0.62, 1.10], p < .001; Std. beta = 0.86, 95%
## CI [0.62, 1.10])
##   - The effect of census division [Mountain] is statistically significant and
## positive (beta = 0.54, 95% CI [0.20, 0.89], p = 0.002; Std. beta = 0.54, 95% CI
## [0.20, 0.89])
##   - The effect of census division [New England] is statistically significant and
## positive (beta = 1.15, 95% CI [0.82, 1.47], p < .001; Std. beta = 1.15, 95% CI
## [0.82, 1.47])
##   - The effect of census division [Pacific] is statistically significant and
## positive (beta = 0.99, 95% CI [0.77, 1.21], p < .001; Std. beta = 0.99, 95% CI
## [0.77, 1.21])
##   - The effect of census division [West North Central] is statistically
## significant and positive (beta = 1.08, 95% CI [0.75, 1.41], p < .001; Std. beta
## = 1.08, 95% CI [0.75, 1.41])
##   - The effect of census division [West South Central] is statistically
## significant and positive (beta = 0.62, 95% CI [0.32, 0.92], p < .001; Std. beta
## = 0.62, 95% CI [0.32, 0.92])
## 
## Standardized parameters were obtained by fitting the model on a standardized
## version of the dataset. 95% Confidence Intervals (CIs) and p-values were
## computed using a Wald z-distribution approximation.
## The marginal R² value of the model is 0.17 and the conditional R² value is 0.947
## The marginal R² represents the proportion of variance explained by the fixed effects ( (Intercept), academicAcademic, insuranceMedicaid, census_divisionEast North Central, census_divisionEast South Central, census_divisionMiddle Atlantic, census_divisionMountain, census_divisionNew England, census_divisionPacific, census_divisionWest North Central, census_divisionWest South Central ) alone ( 17.03 %). The conditional R² represents the proportion of variance explained by both the fixed effects and the random effects ( last ) combined ( 94.66 %). This indicates how much of the variability in the outcome can be attributed to the fixed effects versus the entire model, including random effects.

For poisson_significant model: To determine which random effects were significant in your model, you need to look at the variance components for the random effects and their corresponding standard deviations. In mixed models, random effects themselves do not have p-values like fixed effects do. Instead, you evaluate their significance by looking at the variance of the random effects. If the variance is near zero, the random effect may not be contributing much to the model.

Here’s how you can extract and interpret the variance of the random effects to assess their significance for poisson_significant:

## [1] "The random effects in the model are:\n last"             
## [2] "The random effects in the model are:\n (Intercept)"      
## [3] "The random effects in the model are:\n NA"               
## [4] "The random effects in the model are:\n 0.81442174026169" 
## [5] "The random effects in the model are:\n 0.902453178985863"
## [6] "The random effects in the model are:\n Yes"
## The significant random effects are: last

simr_poisson_full_model Model Power analysis

The power analysis you’ve conducted with the powerSim function is used to estimate the statistical power of your model for detecting effects of a specific predictor—in this case, the predictor insurance in a Poisson mixed-effects model.

Test the poisson_significant model assumptions

Checking the binned residuals because the data is non-parametric the residuals will not be normally distributed. Collinearity was tested as well as heteroscedasticity was checked.

The residuals appear to be spread out more as the fitted values increase. This funnel shape (with wider dispersion of residuals at higher fitted values) is an indication of heteroscedasticity. In a model with homoscedasticity, the residuals would have a consistent spread across all levels of fitted values, without a clear pattern. The data is non-parametric so the residuals will not be within error bounds.

poisson_significant Collinearity

Variance Inflation Factors (VIF) were calculated to assess multicollinearity among predictors. All VIF values were below the commonly used threshold of 5, suggesting that multicollinearity is not a concern for this model.

Variable Importance Factors
GVIF Df GVIF^(1/(2*Df))
academic 1.180096 1 1.086322
insurance 1.025897 1 1.012865
census_division 1.201476 8 1.011538

## OK: No outliers detected.
## - Based on the following method and threshold: cook (0.5).
## - For variable: (Whole model)

poisson Intraclass Correlation Coefficient

The Intraclass Correlation Coefficient (ICC) is a statistical measure used to evaluate the proportion of variance in a dependent variable that can be attributed to differences between groups or clusters. It is commonly used in the context of hierarchical or mixed models to quantify the degree of similarity within clusters.

## The intraclass correlation (ICC) of the model for the random effect group ' last ' is 0.449 .
## This indicates that 44.9 % of the variance in the outcome variable is attributable to differences between the last groups.
## 
##  This is a low to moderate ICC for the last group, indicating that some variance is due to differences between these groups, but a substantial portion is within these groups.

A low to moderate Intraclass Correlation Coefficient (ICC) for the group “physician last name” suggests that while there is some variation in the outcome variable (e.g., business days until appointment) that can be attributed to differences between individual physicians, a substantial portion of the variation occurs within these groups—meaning that much of the variability in appointment times is due to factors other than just the differences between physicians.

In practical terms, this indicates that:

  1. Variation Between Physicians: The fact that the ICC is not zero means that there is some consistency in the appointment times associated with each physician. Some physicians might systematically have longer or shorter wait times, contributing to the variance in the data.

  2. Variation Within Physicians: Since the ICC is low to moderate, it means that even within the same physician, there is considerable variability in appointment times. This could be due to a variety of factors, such as the type of insurance, the scenario, or other factors that are not captured by the physician’s identity alone.

  3. Implications: The low to moderate ICC suggests that while the identity of the physician (as indicated by the last name) does have an effect, it is not the dominant factor driving differences in appointment times. Other factors—potentially those captured by fixed effects or residual variance—are also playing a significant role.

In summary, while who the physician is does matter to some extent, other variables are likely more influential in determining how long a patient waits for an appointment. This insight can guide you to look more closely at those other factors in your analysis or to consider whether there are ways to reduce variability within physicians, such as through standardized scheduling practices.

poisson_significant Dispersion

Overdispersion in your model implies that the variability in the observed data is greater than what the model predicts under the Poisson assumption. Specifically, in a Poisson model, the mean and variance of the count data are assumed to be equal.

## [1] "Significant overdispersion detected. Consider using a Negative Binomial model or adding random effects to account for overdispersion."
## Warning: Autocorrelated residuals detected (p < .001).
## [1] FALSE

Testing assumptions you can use the logLik function to get the log-likelihood of the model, and calculate the residual deviance as -2 * logLik(model). The residual degrees of freedom can be computed as the number of observations minus the number of parameters estimated (which includes both fixed effects and random effects).

The number of parameters estimated can be calculated as the number of fixed effects plus the number of random effects parameters. The number of fixed effects can be obtained from the length of fixef(model), and the number of random effects parameters can be obtained from the length of VarCorr(model).

If the dispersion parameter is considerably greater than 1, it indicates overdispersion. If it is less than 1, it indicates underdispersion. A value around 1 is considered ideal for Poisson regression.

## 'log Lik.' 8.769353 (df=12)

Linearity of logit

The Poisson regression assumes that the log of the expected count is a linear function of the predictors. One way to check this is to plot the observed counts versus the predicted counts and see if the relationship looks linear.

mini_poisson_interaction Model Interactions

To include interaction terms in a regression model, you can use the : operator or the * operator in the formula. The : operator represents the interaction between two variables, while the * operator represents the interaction and also includes the main effects of the two variables. This will include interactions between insurance and each of the other significant variables (academic_affiliation, ACOG_District, central), in addition to the main effects of these variables.

Please note that interpreting interaction effects can be complex, especially in nonlinear models such as Poisson regression. The coefficients for the interaction terms represent the difference in the log rate of days for a one-unit change in x variable, for different levels of the other variables. However, the actual effects on the rate of days can vary depending on the values of the other variables.

\[ \begin{aligned} \text{Business Days Until New Patient Appointment} &\sim \text{Poisson}(\lambda) \\ \log(\lambda) &= \beta_0 \\ &+ \beta_1 \cdot \text{Academic Affiliation} \\ &+ \beta_2 \cdot \text{Patient Insurance} \\ &+ \beta_3 \cdot \text{Census Division} \\ &+ \beta_4 \cdot (\text{Academic Affiliation} \times \text{Patient Insurance}) \\ &+ \beta_5 \cdot (\text{Academic Affiliation} \times \text{Census Division}) \\ &+ \beta_6 \cdot (\text{Patient Insurance} \times \text{Census Division}) \\ &+ \beta_7 \cdot (\text{Academic Affiliation} \times \text{Patient Insurance} \times \text{Census Division}) \\ &+ (1 | \text{Physician Last Name}) \end{aligned} \]

## Generalized linear mixed model fit by maximum likelihood (Laplace
##   Approximation) [glmerMod]
##  Family: poisson  ( log )
## Formula: 
## business_days_until_appointment ~ academic * insurance * census_division +  
##     (1 | phone)
##    Data: df3
##       AIC       BIC    logLik  deviance  df.resid 
##  4800.829  4953.954 -2365.414  4730.829       552 
## Random effects:
##  Groups Name        Std.Dev.
##  phone  (Intercept) 0.8203  
## Number of obs: 587, groups:  phone, 407
## Fixed Effects:
##                                                          (Intercept)  
##                                                              2.31357  
##                                                     academicAcademic  
##                                                             -0.17607  
##                                                    insuranceMedicaid  
##                                                              0.09960  
##                                    census_divisionEast North Central  
##                                                             -0.15256  
##                                    census_divisionEast South Central  
##                                                             -0.23092  
##                                       census_divisionMiddle Atlantic  
##                                                              0.08250  
##                                              census_divisionMountain  
##                                                              0.05387  
##                                           census_divisionNew England  
##                                                              0.38317  
##                                               census_divisionPacific  
##                                                              0.41037  
##                                    census_divisionWest North Central  
##                                                             -0.08351  
##                                    census_divisionWest South Central  
##                                                             -0.09798  
##                                   academicAcademic:insuranceMedicaid  
##                                                              0.23204  
##                   academicAcademic:census_divisionEast North Central  
##                                                              0.60935  
##                   academicAcademic:census_divisionEast South Central  
##                                                              0.48841  
##                      academicAcademic:census_divisionMiddle Atlantic  
##                                                              1.09670  
##                             academicAcademic:census_divisionMountain  
##                                                              0.78108  
##                          academicAcademic:census_divisionNew England  
##                                                             -0.24119  
##                              academicAcademic:census_divisionPacific  
##                                                              0.19614  
##                   academicAcademic:census_divisionWest North Central  
##                                                              0.11508  
##                   academicAcademic:census_divisionWest South Central  
##                                                              1.53571  
##                  insuranceMedicaid:census_divisionEast North Central  
##                                                              0.10925  
##                  insuranceMedicaid:census_divisionEast South Central  
##                                                             -0.08174  
##                     insuranceMedicaid:census_divisionMiddle Atlantic  
##                                                              0.33522  
##                            insuranceMedicaid:census_divisionMountain  
##                                                              0.16489  
##                         insuranceMedicaid:census_divisionNew England  
##                                                              0.29365  
##                             insuranceMedicaid:census_divisionPacific  
##                                                             -0.02951  
##                  insuranceMedicaid:census_divisionWest North Central  
##                                                              0.13197  
##                  insuranceMedicaid:census_divisionWest South Central  
##                                                             -0.17775  
## academicAcademic:insuranceMedicaid:census_divisionEast North Central  
##                                                             -0.66765  
## academicAcademic:insuranceMedicaid:census_divisionEast South Central  
##                                                             -0.02577  
##    academicAcademic:insuranceMedicaid:census_divisionMiddle Atlantic  
##                                                             -0.72816  
##        academicAcademic:insuranceMedicaid:census_divisionNew England  
##                                                              0.19591  
##            academicAcademic:insuranceMedicaid:census_divisionPacific  
##                                                              0.19546  
## academicAcademic:insuranceMedicaid:census_divisionWest North Central  
##                                                              1.14110  
## fit warnings:
## fixed-effect model matrix is rank deficient so dropping 2 columns / coefficients
## optimizer (Nelder_Mead) convergence code: 0 (OK) ; 0 optimizer warnings; 1 lme4 warnings

poisson_significant Interactions

poisson_significant Insurance x academic

## Computing estimated marginal means...
## Estimated data:
##  insurance              academic         rate        SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield Not Academic 11.41071 0.6018770 Inf  10.28998  12.65350
##  Medicaid               Not Academic 13.65751 0.7485234 Inf  12.26648  15.20628
##  Blue Cross/Blue Shield Academic     15.47704 1.4645970 Inf  12.85696  18.63105
##  Medicaid               Academic     18.52450 1.7552107 Inf  15.38489  22.30481
## 
## Results are averaged over the levels of: census_division 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## Range of estimated marginal means with CIs: 10.28998 22.30481 
## Creating the plot...
## Saving plot to: Ari/Figures/interaction_academic_comparison_plot_20240910_214603.png
## Plot saved successfully.
## $data
## academic = Not Academic:
##  insurance                  rate        SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 11.41071 0.6018770 Inf  10.28998  12.65350
##  Medicaid               13.65751 0.7485234 Inf  12.26648  15.20628
## 
## academic = Academic:
##  insurance                  rate        SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 15.47704 1.4645970 Inf  12.85696  18.63105
##  Medicaid               18.52450 1.7552107 Inf  15.38489  22.30481
## 
## Results are averaged over the levels of: census_division 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## $plot

poisson_significant insurance x census divisions

## Computing estimated marginal means...
## Estimated data:
##  insurance              census_division         rate        SE  df asymp.LCL
##  Blue Cross/Blue Shield South Atlantic      6.582068 0.5697977 Inf  5.554889
##  Medicaid               South Atlantic      7.878092 0.6969315 Inf  6.623994
##  Blue Cross/Blue Shield East North Central 15.360221 1.5400081 Inf 12.619914
##  Medicaid               East North Central 18.384683 1.8187654 Inf 15.144266
##  Blue Cross/Blue Shield East South Central  8.306597 0.9550302 Inf  6.630685
##  Medicaid               East South Central  9.942185 1.1527294 Inf  7.921196
##  asymp.UCL
##   7.799187
##   9.369624
##  18.695561
##  22.318452
##  10.406098
##  12.478803
## 
## Results are averaged over the levels of: academic 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## Range of estimated marginal means with CIs: 5.554889 33.0311 
## Creating the plot...
## Saving plot to: Ari/Figures/interaction_insurance_comparison_plot_20240910_214604.png
## Plot saved successfully.
## $data
## census_division = South Atlantic:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield  6.582068 0.569798 Inf  5.554889   7.79919
##  Medicaid                7.878092 0.696931 Inf  6.623994   9.36962
## 
## census_division = East North Central:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 15.360221 1.540008 Inf 12.619914  18.69556
##  Medicaid               18.384683 1.818765 Inf 15.144266  22.31845
## 
## census_division = East South Central:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield  8.306597 0.955030 Inf  6.630685  10.40610
##  Medicaid                9.942185 1.152729 Inf  7.921196  12.47880
## 
## census_division = Middle Atlantic:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 15.584697 1.738723 Inf 12.523714  19.39383
##  Medicaid               18.653359 2.085594 Inf 14.982558  23.22353
## 
## census_division = Mountain:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 11.339279 1.987324 Inf  8.042734  15.98701
##  Medicaid               13.572009 2.386715 Inf  9.615137  19.15723
## 
## census_division = New England:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 20.702493 3.053952 Inf 15.504461  27.64322
##  Medicaid               24.778861 3.634199 Inf 18.588297  33.03110
## 
## census_division = Pacific:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 17.777620 1.817992 Inf 14.548803  21.72301
##  Medicaid               21.278074 2.201240 Inf 17.372990  26.06094
## 
## census_division = West North Central:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 19.339858 3.077697 Inf 14.157781  26.41870
##  Medicaid               23.147920 3.706487 Inf 16.912820  31.68166
## 
## census_division = West South Central:
##  insurance                   rate       SE  df asymp.LCL asymp.UCL
##  Blue Cross/Blue Shield 12.237311 1.668419 Inf  9.367729  15.98592
##  Medicaid               14.646865 2.009639 Inf 11.193209  19.16614
## 
## Results are averaged over the levels of: academic 
## Confidence level used: 0.95 
## Intervals are back-transformed from the log scale 
## 
## $plot

fin

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