Appendix Table 2.
Logistic Regression of Variables Associated with Achieving MCID at 6 Months and 1 Year
| Questionnaire | Factor | 6 Months |
12 Months |
||||
|---|---|---|---|---|---|---|---|
| Univariate | Multivariate | OR (95% CI) | Univariate | Multivariate | OR (95% CI) | ||
| IKDC | Sex | 0.850 | 1.111 (0.372 – 3.320) | 0.860 | 0.897 (0.269 – 2.988) | ||
| Age | 0.004 | 0.001 | 0.861 (0.789 – 0.939) | 0.446 | 0.975 (0.914 – 1.040) | ||
| BMI | 0.174 | 0.950 (0.883 – 1.022) | 0.477 | 0.972 (0.898 – 1.052) | |||
| WC | 0.134 | 0.148 (0.013 – 1.722) | 0.930 | 1.118 (0.095 – 13.150) | |||
| Age at First Instability Event | 0.137 | 0.972 (0.908 – 1.040) | 0.562 | 1.023 (0.948 – 1.103) | |||
| Number of Instability Events | 0.483 | 0.989 (0.958 – 1.020) | 0.253 | 0.954 (0.880 – 1.034) | |||
| Preoperative PRO Score | 0.027 | 0.004 | 0.946 (0.911 – 0.983) | 0.010 | 0.954 (0.921 – 0.989) | ||
| KOOS Symptoms | Sex | 0.313 | 0.478 (0.114 – 2.004) | 0.509 | 1.625 (0.384 – 6.872) | ||
| Age | 0.803 | 1.010 (0.933 – 1.094) | 0.342 | 1.049 (0.950 – 1.159) | |||
| BMI | 0.093 | .901 | 1.009 (0.877 – 1.160) | 0.260 | 1.061 (0.957 – 1.177) | ||
| WC | 0.685 | 0.556 (0.032 – 9.535) | 0.878 | 0.800 (0.046 – 13.812) | |||
| Age at First Instability Event | 0.828 | 0.992 (0.919 – 1.070) | 0.158 | 1.087 (0.968 – 1.219) | |||
| Number of Instability Events | 0.261 | 1.160 (0.895 – 1.503) | 0.397 | 0.944 (0.826 – 1.079) | |||
| Preoperative PRO Score | 0.001 | 0.002 | 0.911 (0.857 – 0.967) | 0.004 | 0.906 (0.847 – 0.968) | ||
| KOOS Pain | Sex | 0.234 | 0.417 (0.098 – 1.763) | 0.740 | 0.762 (0.153 – 3.802) | ||
| Age | 0.600 | 1.022 (0.942 – 1.110) | 0.484 | 1.043 (0.926 – 1.176) | |||
| BMI | 0.137 | 1.091 (0.973 – 1.122) | 0.289 | 1.081 (0.936 – 1.247) | |||
| WC | 0.633 | 0.726 (0.029 – 8.602) | predicts success perfectly | ||||
| Age at First Instability Event | 0.105 | 1.089 (0.982 – 1.208) | 0.078 | 0.176 | 1.1456 (0.941 – 1.340) | ||
| Number of Instability Events | 0.355 | 0.964 (0.891 – 1.042) | 0.170 | 0.791 (0.565 – 1.106) | |||
| Preoperative PRO Score | 0.032 | 0.961 (0.926 – 0.996) | 0.036 | 0.100 | 0.949 (0.890 – 1.010) | ||
| KOOS ADL | Sex | 0.229 | 0.413 (0.098 – 1.745) | 0.885 | 1.123 (0.235 – 5.359) | ||
| Age | 0.910 | 1.004 (0.930 – 1.085) | 0.426 | 1.046 (0.936 – 1.170) | |||
| BMI | 0.212 | 1.064 (0.965 – 1.173) | 0.321 | 1.065 (0.941 – 1.204) | |||
| WC | 0.843 | 0.750 (0.044 – 12.816) | 0.513 | 0.385 (0.022 – 6.757) | |||
| Age at First Instability Event | 0.284 | 1.046 (0.964 – 1.134) | 0.065 | 0.205 | 1.157 (0.923 – 1.451) | ||
| Number of Instability Events | 0.299 | 0.950 (0.863 – 1.047) | 0.298 | 0.917 (0.780 – 1.079) | |||
| Preoperative PRO Score | 0.001 | 0.878 (0.814 – 0.948) | 0.007 | 0.032 | 0.912 (0.839 – 0.992) | ||
| KOOS Sport | Sex | 0.456 | 2.333 (0.252 – 21.634) | 0.355 | 0.505 (0.119 – 2.145) | ||
| Age | 0.539 | 0.971 (0.882 – 1.068) | 0.919 | 1.005 (0.909 – 1.112) | |||
| BMI | 0.275 | 1.086 (0.936 – 1.261) | 0.568 | 0.973 (0.884 – 1.070) | |||
| WC | 0.275 | 0.200 (0.011 – 3.592) | 0.634 | 0.500 (0.029 – 8.706) | |||
| Age at First Instability Event | 0.949 | 0.997 (0.906 – 1.096) | 0.450 | 1.044 (0.934 – 1.167) | |||
| Number of Instability Events | 0.692 | 1.027 (0.901 – 1.170) | 0.304 | 0.931 (0.811 – 1.067) | |||
| Preoperative PRO Score | 0.096 | 0.974 (0.944 – 1.005) | 0.092 | 0.976 (0.948 – 1.004) | |||
| KOOS QOL | Sex | 0.679 | 0.718 (0.150 – 3.442) | predicts success perfectly | Collinearity | ||
| Age | 0.731 | 0.985 (0.904 – 1.074) | 0.712 | 1.032 (0.875 – 1.216) | |||
| BMI | 0.390 | 1.052 (0.937 – 1.180) | 0.854 | 1.015 (0.865 – 1.191) | |||
| WC | 0.426 | 0.313 (0.179 – 5.464) | predicts success perfectly | ||||
| Age at First Instability Event | 0.421 | 1.040 (0.945 – 1.145) | 0.444 | 1.074 (0.895 – 1.289) | |||
| Number of Instability Events | 0.171 | 1.310 (0.890 – 1.929) | 0.975 | 1.002 (0.859 – 1.170) | |||
| Preoperative PRO Score | 0.084 | 0.970 (0.936 – 1.004) | 0.522 | 1.025 (0.951 – 1.105) | |||
| Kujala Function | Sex | 0.387 | 0.500 (0.104 – 2.403) | predicts success perfectly | Collinearity | ||
| Age | 0.755 | 0.981 (0.890 – 1.088) | predicts success perfectly | ||||
| BMI | 0.699 | 0.980 (0.886 – 1.085) | predicts success perfectly | ||||
| WC | 0.324 | 0.280 (0.022 – 3.506) | predicts success perfectly | ||||
| Age at First Instability Event | 0.551 | 0.969 (0.873 – 1.075) | predicts success perfectly | ||||
| Number of Instability Events | 0.931 | 1.002 (0.950 – 1.058) | 0.369 | 0.741 (0.386 – 1.424) | |||
| Preoperative PRO Score | 0.088 | 0.959 (0.913 – 1.006) | predicts success perfectly | ||||
| Kujala Symptoms | Sex | 0.856 | 1.143 (0.269 – 4.859) | predicts success perfectly | Collinearity | ||
| Age | 0.051 | 0.013 | 0.862 (0.766 – 0.970) | predicts success perfectly | |||
| BMI | 0.298 | 0.957 (0.881 – 1.040) | predicts success perfectly | ||||
| WC | 0.094 | 0.234 | 0.182 (0.011 – 3.000) | predicts success perfectly | |||
| Age at First Instability Event | 0.214 | 0.947 (0.870 – 1.032) | predicts success perfectly | ||||
| Number of Instability Events | 0.188 | 0.976 (0.942 – 1.012) | 0.369 | 0.741 (0.386 – 1.424) | |||
| Preoperative PRO Score | 0.043 | 0.007 | 0.931 (0.884 – 0.980) | predicts success perfectly | |||
| KOOS JR Pain | Sex | 0.894 | 1.071 (0.387 – 2.968) | 0.932 | 1.067 (0.241 – 4.715) | ||
| Age | 0.792 | 1.008 (0.947 – 1.074) | 0.968 | 1.002 (0.903 – 1.112) | |||
| BMI | 0.204 | 1.051 (0.973 – 1.135) | 0.591 | 1.031 (0.923 – 1.152) | |||
| WC | 0.925 | 1.125 (0.097 – 12.989) | predicts success perfectly | ||||
| Age at First Instability Event | 0.659 | 1.015 (0.950 – 1.085) | 0.099 | 0.830 | 1.023 (0.830 – 1.260) | ||
| Number of Instability Events | 0.431 | 1.017 (0.975 – 1.060) | 0.098 | 0.130 | 0.922 (0.830 – 1.024) | ||
| Preoperative PRO Score | 0.066 | 0.969 (0.937 – 1.002) | 0.087 | 0.020 | 0.907 (0.835 – 0.985) | ||
| KOOS JR Symptoms | Sex | 0.894 | 1.071 (0.387 – 2.968) | 0.631 | 1.429 (0.333 – 6.131) | ||
| Age | 0.972 | 1.009 (0.947 – 1.074) | 0.649 | 1.024 (0.926 – 1.132) | |||
| BMI | 0.204 | 1.051 (0.973 – 1.135) | 0.381 | 1.050 (0.941 – 1.172) | |||
| WC | 0.925 | 1.125 (0.097 – 12.989) | predicts success perfectly | ||||
| Age at First Instability Event | 0.659 | 1.015 (0.950 – 1.085) | 0.109 | 1.138 (0.972 – 1.333) | |||
| Number of Instability Events | 0.431 | 1.017 (0.975 – 1.060) | 0.156 | 0.944 (0.871 – 1.022) | |||
| Preoperative PRO Score | 0.066 | 0.969 (0.937 – 1.002) | 0.003 | 0.899 (0.839 – 0.964) | |||
| KOOS JR ADL | Sex | 0.894 | 1.071 (0.387 – 2.968) | 0.631 | 1.429 (0.333 – 6.131) | ||
| Age | 0.792 | 1.009 (0.947 – 1.074) | 0.649 | 1.024 (0.926 – 1.132) | |||
| BMI | 0.204 | 1.051 (0.973 – 1.135) | 0.381 | 1.050 (0.941 – 1.172) | |||
| WC | 0.925 | 1.125 (0.097 – 12.989) | predicts success perfectly | ||||
| Age at First Instability Event | 0.659 | 1.015 (0.950 – 1.085) | 0.109 | 1.138 (0.971 – 1.333) | |||
| Number of Instability Events | 0.431 | 1.017 (0.975 – 1.060) | 0.156 | 0.944 (0.871 – 1.022) | |||
| Preoperative PRO Score | 0.066 | 0.969 (0.937- 1.002) | 0.003 | 0.899 (0.837 – 0.964) | |||
Bold indicates significant value (P < .05 and OR does not cross 1.0). All univariate and multivariate analyses reported as P values. Odds Ratio is reported for multivariate regression if significant, otherwise corresponds to univariate regression.OR, odds ratio; 95% CI, 95% confidence interval; MCID, minimal clinically important difference; IKDC, International Knee Documentation Committee; KOOS, Knee Injury and Osteoarthritis Outcome Score; ADL, activities of daily living; QOL, quality of life; JR, joint replacement; BMI, body mass index; WC, workers’ compensation; PRO, patient-reported outcome.