After exploring the data, we found that the main concern of missingness is about “fxtosurgwk” and outcome “chronicpain”.
We divide the data into two groups according to the missingness of outcome “chronic_pain” . Then we compare two groups in term of all other variables.
For continuous variables, we use two sample paired t-test, and for categorical variables, we use pearson chi square test. The following are the p-values of all other variables, under the null hypothesis that for every single variable, two groups have the same distribution.
| with missing outcome | with observed outcome | p.value | |
|---|---|---|---|
| astreat exfix | 13 (33.3%) | 47 (32.4%) | 0.789 |
| astreat pinning | 12 (30.8%) | 38 (26.2%) | . |
| astreat VLPS | 14 (35.9%) | 60 (41.4%) | . |
| gender male | 4 (10.3%) | 18 (12.4%) | 0.928 |
| gender female | 35 (89.7%) | 127 (87.6%) | . |
| rapa active | 13 (33.3%) | 69 (47.9%) | 0.26 |
| rapa underactive | 21 (53.8%) | 62 (43.1%) | . |
| rapa sedentary | 5 (12.8%) | 13 (9%) | . |
| osteoatrts_yes no | 26 (68.4%) | 92 (63.4%) | 0.704 |
| osteoatrts_yes yes | 12 (31.6%) | 53 (36.6%) | . |
smoke simple Yes |
23 (60.5%) | 64 (44.1%) | 0.106 |
smoke simple No |
15 (39.5%) | 81 (55.9%) | . |
education simple < high school |
6 (16.2%) | 13 (9.2%) | 0.354 |
education simple high |
31 (83.8%) | 128 (90.8%) | . |
| income 10-30K | 14 (41.2%) | 31 (25.4%) | 0.114 |
| income >60K | 11 (32.4%) | 46 (37.7%) | . |
| income 30-60K | 9 (26.5%) | 45 (36.9%) | . |
| employ retired | 18 (54.5%) | 103 (71%) | 0.104 |
| employ fulltime | 15 (45.5%) | 42 (29%) | . |
| inj_dom No | 24 (70.6%) | 78 (54.2%) | 0.122 |
| inj_dom Yes | 10 (29.4%) | 66 (45.8%) | . |
| usfx Yes | 10 (27.8%) | 65 (46.8%) | 0.063 |
| usfx No | 26 (72.2%) | 74 (53.2%) | . |
ao simple A |
20 (55.6%) | 87 (63%) | 0.529 |
ao simple C |
16 (44.4%) | 51 (37%) | . |
| fxtosurgwk | 1.3 (0.74) | 1.2 (0.68) | 0.402 |
| age | 66.7 (6.88) | 68.9 (7.18) | 0.08 |
| nocomorb | 3.7 (2.68) | 3.3 (2.18) | 0.391 |
| b_radhi | 7.9 (4.26) | 8.4 (3.36) | 0.527 |
| b_radinc | 15.8 (7.62) | 16.1 (5.34) | 0.812 |
| b_vdtilt | -13.1 (15.13) | -14.5 (13.59) | 0.609 |
| b_ulnavar | 1.5 (2.57) | 2.6 (2.98) | 0.035 |
| b_PCS | 33.2 (9.76) | 34.3 (10.38) | 0.535 |
| b_MCS | 47.6 (13.43) | 50.2 (13.88) | 0.297 |
| b_painnorm | 6.8 (15.91) | 3.2 (10.94) | 0.194 |
| b_paindiff | 63.2 (27.78) | 60.8 (27.65) | 0.628 |
## glm(formula = miss_y ~ ., family = binomial(link = "logit"),
## data = D)
## Estimate Std. Error p.value significance
## (Intercept) -10.78 1466.08 0.994
## as.factor.dat.astreat.pinning -0.49 0.89 0.583
## as.factor.dat.astreat.VLPS -1.30 1.02 0.201
## as.factor.dat.gender.male 0.23 1.19 0.849
## as.factor.dat.rapa.sedentary 1.40 1.60 0.381
## as.factor.dat.rapa.underactive 0.87 0.79 0.275
## as.factor.dat.osteoatrts_yes.yes -1.34 1.12 0.233
## as.factor.dat..smoke.simple..Yes 0.71 0.83 0.395
## as.factor.dat..education.simple..high -4.86 1.81 0.007 **
## as.factor.dat.income.>60K 22.46 1466.07 0.988
## as.factor.dat.income.10-30K 23.11 1466.07 0.987
## as.factor.dat.income.30-60K 21.91 1466.07 0.988
## as.factor.dat.employ.retired -2.01 1.07 0.060 .
## as.factor.dat.inj_dom.Yes -0.89 0.78 0.252
## as.factor.dat.usfx.Yes -1.98 0.95 0.037 *
## as.factor.dat..ao.simple..C 1.45 0.81 0.073 .
## dat.fxtosurgwk 0.83 0.56 0.140
## dat.age -0.13 0.10 0.185
## dat.nocomorb 0.01 0.18 0.972
## dat.b_radhi 0.05 0.17 0.776
## dat.b_radinc -0.11 0.11 0.339
## dat.b_vdtilt -0.03 0.03 0.317
## dat.b_ulnavar -0.55 0.25 0.030 *
## dat.b_PCS 0.00 0.04 0.945
## dat.b_MCS 0.00 0.03 0.885
## dat.b_painnorm 0.01 0.03 0.818
## dat.b_paindiff 0.02 0.02 0.340
We use inverse-propensity as every sample’s weight to fit a logistic regression.
## glm(formula = y0 ~ ., family = binomial(link = "logit"), data = D,
## weights = w)
## Estimate Std. Error p.value significance
## (Intercept) -1.47 3.59 0.683
## as.factor.dat.astreat.pinning 0.06 0.69 0.926
## as.factor.dat.astreat.VLPS -1.58 0.65 0.014 *
## as.factor.dat.gender.male 1.36 0.88 0.123
## as.factor.dat.rapa.sedentary -1.27 0.95 0.182
## as.factor.dat.rapa.underactive 0.12 0.50 0.817
## as.factor.dat.osteoatrts_yes.yes 0.57 0.59 0.331
## as.factor.dat..smoke.simple..Yes 0.69 0.50 0.167
## as.factor.dat..education.simple..high -0.80 1.05 0.445
## as.factor.dat.income.>60K 1.23 1.13 0.274
## as.factor.dat.income.10-30K 0.79 1.10 0.474
## as.factor.dat.income.30-60K -0.12 1.04 0.910
## as.factor.dat.employ.retired 0.46 0.56 0.415
## as.factor.dat.inj_dom.Yes -0.49 0.47 0.297
## as.factor.dat.usfx.Yes -0.07 0.46 0.886
## as.factor.dat..ao.simple..C 0.20 0.51 0.700
## dat.fxtosurgwk 1.28 0.39 0.001 **
## dat.age 0.01 0.04 0.751
## dat.nocomorb -0.07 0.14 0.621
## dat.b_radhi -0.04 0.12 0.720
## dat.b_radinc 0.06 0.07 0.427
## dat.b_vdtilt -0.02 0.02 0.216
## dat.b_ulnavar 0.07 0.09 0.392
## dat.b_PCS -0.01 0.03 0.800
## dat.b_MCS -0.03 0.02 0.068 .
## dat.b_painnorm -0.01 0.02 0.765
## dat.b_paindiff 0.01 0.01 0.277
## glm(formula = y0 ~ as.factor.dat.astreat. + as.factor.dat.gender. +
## as.factor.dat..smoke.simple.. + dat.fxtosurgwk + dat.b_vdtilt +
## dat.b_MCS + dat.b_paindiff, family = binomial(link = "logit"),
## data = D, weights = w)
## Estimate Std. Error p.value significance
## (Intercept) -0.95 1.13 0.400
## as.factor.dat.astreat.pinning 0.37 0.55 0.499
## as.factor.dat.astreat.VLPS -1.37 0.52 0.009 **
## as.factor.dat.gender.male 1.11 0.65 0.089 .
## as.factor.dat..smoke.simple..Yes 0.69 0.43 0.108
## dat.fxtosurgwk 1.02 0.33 0.002 **
## dat.b_vdtilt -0.02 0.02 0.137
## dat.b_MCS -0.02 0.02 0.099 .
## dat.b_paindiff 0.02 0.01 0.021 *