Table 5.
Logistic regression models of run-in failure: two-group randomization females
| Unadjusted OR (95 % CI)a | p | Final model: adjusted OR (95 % CI) C index = 0.79 | p | Final model + perceived toxicity adjusted OR (95 % CI)b C index = 0.81 | p | |
|---|---|---|---|---|---|---|
| Total participants | N = 659 | N = 659 | ||||
| Race | 0.01 | |||||
| White | Reference | |||||
| Black | 2.44 (1.29–4.62) | |||||
| Other | 0.48 (0.06–3.66) | |||||
| Unknown/refused | 2.50 (1.21–5.17) | |||||
| Marital status | 0.04 | |||||
| Married/cohabitating | Reference | |||||
| Single | 1.66 (1.03–2.69) | |||||
| Education | 0.03 | |||||
| Did not graduate high school | 2.38 (1.21–4.69) | |||||
| Graduated high school | 1.52 (0.82–2.83) | |||||
| Any college education | Reference | |||||
| Taking a multivitaminc | 0.001 | 0.002 | 0.004 | |||
| No | Reference | Reference | Reference | |||
| Yes | 0.44 (0.27–0.71) | 0.44 (0.26–0.75) | 0.45 (0.26–0.77) | |||
| Taking calcium supplementsc | 0.001 | |||||
| No | Reference | |||||
| Yes | 0.45 (0.28–0.73) | |||||
| Taking vitamin D supplementsc | ||||||
| No | Reference | 0.0003 | ||||
| Yes | 0.31 (0.16–0.58) | |||||
| SF-36 mental component summary measure (per 5 units) | 0.81 (0.70–0.94) | 0.01 | ||||
| SF-36 physical component summary measure (per 5 units) | 0.75 (0.65–0.86) | <0.0001 | 0.73 (0.62–0.86) | 0.0002 | 0.70 (0.58–0.83) | <0.0001 |
| Study center | <0.0001 | <0.0001 | <0.0001 | |||
| A | Reference | Reference | Reference | |||
| B | 1.51 (0.29–7.74) | 0.86 (0.14–5.42) | 1.00 (0.15–6.56) | |||
| C | 1.27 (0.21–7.90) | 1.39 (0.22–8.82) | 1.68 (0.25–11.13) | |||
| D | 1.33 (0.22–8.28) | 1.07 (0.17–6.85) | 1.23 (0.19–8.17) | |||
| E | 2.24 (0.52–9.72) | 1.84 (0.42–8.18) | 1.88 (0.40–8.85) | |||
| F | 14.67 (4.16–51.74) | 13.17 (3.65–47.58) | 14.37 (3.76–55.00) | |||
| G | 1.85 (0.40–8.56) | 2.02 (0.43–9.52) | 1.97 (0.38–10.30) | |||
| H | 6.31 (1.68–23.69) | 4.90 (1.28–18.80) | 5.32 (1.31–21.53) | |||
| I | 5.50 (1.52–19.88) | 5.58 (1.51–20.68) | 6.18 (1.58–24.18) | |||
| J | 6.37 (0.94–43.30) | 5.36 (0.73–39.45) | 6.63 (0.85–51.46) | |||
| K | 7.72 (2.12–28.14) | 4.12 (1.06–15.97) | 3.12 (0.75–13.02) | |||
| Colonoscopy surveillance interval | 0.004 | 0.03 | 0.02 | |||
| 3 years | Reference | Reference | Reference | |||
| 5 years | 2.08 (1.27–3.41) | 1.91 (1.08–3.37) | 2.06 (1.13–3.74) | |||
| Refused any questions during enrollment intake questionnaired | 0.01 | |||||
| No | Reference | |||||
| Yes | 22.14 (2.28–215.43) | |||||
| Answered ”Don’t know” to any questions during enrollment intake questionnaired | 0.05 | |||||
| No | Reference | |||||
| Yes | 1.85 (1.00–3.43) | |||||
| Refused any questions during enrollment self-administered questionnairesd | 0.002 | |||||
| No | Reference | |||||
| Yes | 2.49 (1.42–4.38) | |||||
| Counseled at baseline to change dietd | 0.07 | |||||
| No | Reference | |||||
| Yes | 3.71 (0.91–15.12) | |||||
| Improve mood | 0.06 | |||||
| Very/somewhat likely | Reference | |||||
| Don’t know | 0.54 (0.32–0.92) | |||||
| Very/somewhat unlikely | 0.65 (0.33–1.29) | |||||
| Cause constipation | 0.10 | |||||
| Very/somewhat likely | Reference | |||||
| Don’t know | 0.55 (0.31–0.96) | |||||
| Very/somewhat unlikely | 0.61 (0.33–1.12) | |||||
| Had a perceived toxicity during the run-in period | <0.0001 | |||||
| No | Reference | |||||
| Yes | 29.02 (6.83–123.33) | |||||
aIncluded were all variables that had p < 0.1 from Table 1 and baseline factors from Table 2
bFinal model plus perceived toxicity, the post-enrollment factor from Table 2
cBaseline multivitamin, calcium, and vitamin D supplement use were collinear variables; the first was included in the model
dNot a priori potential predictors