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.
id_number | physician_information | N |
---|---|---|
NA | NA | NA |
———: | :——————— | –: |
## File saved to: ortho_sports_med/Figures/quality_check_table2.csv
id_number | physician_information | reason_for_exclusions | insurance | business_days_until_appointment |
---|---|---|---|---|
NA | NA | NA | NA | NA |
———: | :——————— | :——————— | :——— | ——————————-: |
physician_information | calls_count |
---|---|
NA | NA |
:——————— | ———–: |
## File saved to: ortho_sports_med/Figures/discrepancy_rows.csv
physician_information | id_number | notes | reason_for_exclusions | business_days_until_appointment |
---|---|---|---|---|
NA | NA | NA | NA | NA |
:——————— | ———: | :—– | :——————— | ——————————-: |
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 |
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%.
## 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 ).
The median physician age was 55(IQR 25th percentile 48 to 75th percentile 62).
## 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%).
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)
Wait Time with single predictor
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
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.
scenario | Median_business_days_until_appointment | Q1 | Q3 |
---|---|---|---|
HIP scenario | 12 | 6 | 22 |
KNEE scenario | 12 | 6 | 21 |
SHOULDER scenario | 11 | 6 | 20 |
business_days_until_appointment ~ scenario
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.
business_days_until_appointment ~ 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.
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.
Graph each variable
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%) |
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 | |||
|
113 (32.5%) | 47 (26.7%) | 160 (30.5%) | |
|
71 (20.4%) | 25 (14.2%) | 96 (18.3%) | |
|
58 (16.7%) | 43 (24.4%) | 101 (19.3%) | |
|
54 (15.5%) | 25 (14.2%) | 79 (15.1%) | |
|
52 (14.9%) | 36 (20.5%) | 88 (16.8%) | |
Orthopedist Gender | 0.27 | |||
|
22 (6.3%) | 7 (4.0%) | 29 (5.5%) | |
|
326 (93.7%) | 169 (96.0%) | 495 (94.5%) | |
Medical School Training | 0.27 | |||
|
9 (2.6%) | 2 (1.1%) | 11 (2.1%) | |
|
339 (97.4%) | 174 (98.9%) | 513 (97.9%) | |
Academic Affiliation | < 0.01 | |||
|
63 (18.1%) | 16 (9.1%) | 79 (15.1%) | |
|
285 (81.9%) | 160 (90.9%) | 445 (84.9%) | |
US Census Bureau Subdivision | 0.03 | |||
|
48 (13.8%) | 14 (8.1%) | 62 (11.9%) | |
|
31 (8.9%) | 8 (4.7%) | 39 (7.5%) | |
|
45 (12.9%) | 30 (17.4%) | 75 (14.4%) | |
|
25 (7.2%) | 11 (6.4%) | 36 (6.9%) | |
25 (7.2%) | 9 (5.2%) | 34 (6.5%) | ||
|
51 (14.7%) | 30 (17.4%) | 81 (15.6%) | |
|
74 (21.3%) | 31 (18.0%) | 105 (20.2%) | |
|
18 (5.2%) | 9 (5.2%) | 27 (5.2%) | |
|
31 (8.9%) | 30 (17.4%) | 61 (11.7%) | |
Rurality | 0.39 | |||
|
318 (91.6%) | 165 (93.8%) | 483 (92.4%) | |
|
29 (8.4%) | 11 (6.2%) | 40 (7.6%) | |
Number of Phone Transfers | 0.02 | |||
|
119 (34.2%) | 83 (47.4%) | 202 (38.6%) | |
|
161 (46.3%) | 68 (38.9%) | 229 (43.8%) | |
|
57 (16.4%) | 18 (10.3%) | 75 (14.3%) | |
|
11 (3.2%) | 6 (3.4%) | 17 (3.3%) | |
Insurance | < 0.01 | |||
|
152 (43.7%) | 0 (0.0%) | 152 (29.0%) | |
|
196 (56.3%) | 176 (100.0%) | 372 (71.0%) | |
Orthopedic Scenario | 0.68 | |||
|
120 (34.5%) | 54 (30.7%) | 174 (33.2%) | |
|
109 (31.3%) | 58 (33.0%) | 167 (31.9%) | |
|
119 (34.2%) | 64 (36.4%) | 183 (34.9%) | |
Central Scheduling | 0.04 | |||
|
215 (61.8%) | 125 (71.0%) | 340 (64.9%) | |
|
133 (38.2%) | 51 (29.0%) | 184 (35.1%) | |
Call time (minutes) | < 0.01 | |||
|
312 | 152 | 464 | |
|
3.0 (1.7, 4.1) | 1.5 (1.0, 2.8) | 2.4 (1.3, 4.0) | |
Hold time (minutes) | 0.59 | |||
|
259 | 124 | 383 | |
|
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 | |||
|
99 (28.4%) | 69 (39.2%) | 168 (32.1%) | |
|
83 (23.9%) | 29 (16.5%) | 112 (21.4%) | |
|
114 (32.8%) | 45 (25.6%) | 159 (30.3%) | |
|
37 (10.6%) | 15 (8.5%) | 52 (9.9%) | |
|
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.
Accepts Medicaid and/or BCBS (N=266) | Does Not Accept Medicaid (N=234) | Total (N=500) | p value | |
---|---|---|---|---|
business_days_until_appointment | ||||
|
13.0 (7.0, 23.0) | NA | 13.0 (7.0, 23.0) | |
age | < 0.01 | |||
|
53.0 (48.0, 60.5) | 56.0 (49.0, 63.0) | 55.0 (48.0, 62.0) | |
gender | 0.52 | |||
|
16 (6.0%) | 11 (4.7%) | 27 (5.4%) | |
|
250 (94.0%) | 223 (95.3%) | 473 (94.6%) | |
Provider.Credential.Text | 0.48 | |||
|
7 (2.6%) | 4 (1.7%) | 11 (2.2%) | |
|
259 (97.4%) | 230 (98.3%) | 489 (97.8%) | |
academic | < 0.01 | |||
|
53 (19.9%) | 21 (9.0%) | 74 (14.8%) | |
|
213 (80.1%) | 213 (91.0%) | 426 (85.2%) | |
census_division | < 0.01 | |||
|
44 (16.5%) | 17 (7.4%) | 61 (12.3%) | |
|
26 (9.8%) | 13 (5.7%) | 39 (7.9%) | |
|
27 (10.2%) | 44 (19.1%) | 71 (14.3%) | |
|
19 (7.1%) | 13 (5.7%) | 32 (6.5%) | |
|
23 (8.6%) | 9 (3.9%) | 32 (6.5%) | |
|
32 (12.0%) | 46 (20.0%) | 78 (15.7%) | |
|
58 (21.8%) | 41 (17.8%) | 99 (20.0%) | |
|
17 (6.4%) | 9 (3.9%) | 26 (5.2%) | |
|
20 (7.5%) | 38 (16.5%) | 58 (11.7%) | |
scenario | 0.40 | |||
|
93 (35.0%) | 74 (31.6%) | 167 (33.4%) | |
|
76 (28.6%) | 80 (34.2%) | 156 (31.2%) | |
|
97 (36.5%) | 80 (34.2%) | 177 (35.4%) | |
call_date_wday | 0.35 | |||
|
23 (8.6%) | 34 (14.5%) | 57 (11.4%) | |
|
91 (34.2%) | 70 (29.9%) | 161 (32.2%) | |
|
39 (14.7%) | 31 (13.2%) | 70 (14.0%) | |
|
58 (21.8%) | 59 (25.2%) | 117 (23.4%) | |
|
55 (20.7%) | 40 (17.1%) | 95 (19.0%) | |
central_number | 0.20 | |||
|
171 (64.3%) | 163 (69.7%) | 334 (66.8%) | |
|
95 (35.7%) | 71 (30.3%) | 166 (33.2%) | |
number_of_transfers | < 0.01 | |||
|
77 (28.9%) | 108 (46.4%) | 185 (37.1%) | |
|
131 (49.2%) | 91 (39.1%) | 222 (44.5%) | |
|
45 (16.9%) | 27 (11.6%) | 72 (14.4%) | |
|
13 (4.9%) | 7 (3.0%) | 20 (4.0%) | |
call_time_minutes | < 0.01 | |||
|
3.1 (2.0, 4.6) | 1.4 (1.0, 2.8) | 2.3 (1.2, 4.1) | |
hold_time_minutes | 0.48 | |||
|
0.5 (0.1, 2.2) | 0.5 (0.0, 2.0) | 0.5 (0.0, 2.0) | |
insurance | 0.35 | |||
|
1 (0.4%) | 0 (0.0%) | 1 (0.2%) | |
|
265 (99.6%) | 234 (100.0%) | 499 (99.8%) | |
does_the_physician_accept_medicaid | < 0.01 | |||
|
0 (0.0%) | 58 (24.8%) | 58 (11.6%) | |
0 (0.0%) | 176 (75.2%) | 176 (35.2%) | ||
|
266 (100.0%) | 0 (0.0%) | 266 (53.2%) |
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.
## 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.
## 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
## 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
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.
## [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.
## [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
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.
## 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.
## 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
## 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
## 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).
poisson_full_model
$$ \[\begin{align*} P(\text{{Business Days until New Patient Appointment}} = x) &= \frac{e^{-\lambda} \cdot \lambda^x}{x!} \\ \sqrt{\lambda} &= \beta_0 \\ & + \beta_1 \cdot \text{{Patient Insurance}} \\ & + \beta_2 \cdot \text{{US Census Bureau Subdivision}} \\ & + \beta_3 \cdot \text{{Physician Academic Affiliation}} \\ & + \beta_4 \cdot \text{{Physician Age}} \\ & + \beta_5 \cdot \text{{Physician Gender}} \\ & + \beta_6 \cdot \text{{Physician Honorrific}} \\ & + \beta_7 \cdot \text{{Physician US Census Bureau}} \\ & + \beta_8 \cdot \text{{Hip, Shoulder, Knee Scenario}} \\ & + \beta_9 \cdot \text{{Date that the call was made}} \\ & + \beta_10 \cdot \text{{Appointment Central Number}} \\ & + \beta_11 \cdot \text{{Number of Phone Transfers}} \\ & + \beta_12 \cdot \text{{Minutes on the phone}} \\ & + \beta_13 \cdot \text{{Minutes on hold}} \\ & + \beta_14 \cdot \text{{Rurality}} \\ & + ( 1 | \text{{Physician Last Name}}) \end{align*}\] $$
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
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
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.
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
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 |
poisson_significant
modelFixed
Effectspoisson_significant
Model
Predictionspoisson_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 analysisThe 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.
poisson_significant
model assumptionsChecking 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
CollinearityVariance 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.
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 CoefficientThe 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:
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.
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.
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
DispersionOverdispersion 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)
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 InteractionsTo 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
Interactionspoisson_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
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