Table 2 Hazard ratios for sick leave> 90 days/disability pension with 95% confidence intervals
|  | Crude | Adjusted sex, age and education | Adjusted for all significant variables | Co-twin analyses of discordant twin pairs (n = 140 pairs) |
|---|---|---|---|---|
Sex | ||||
 Male | 0.56 (0.47–0.65) |  | 0.57 (0.47–0.69) |  |
 Female | ref |  | ref |  |
Age | ||||
 19–28 | 0.62 (0.49–0.78) |  | 0.53 (0.41–0.69) |  |
 29–37 | 0.85 (0.73–0.99) |  | 0.84 (0.71–1.01) |  |
 38–47 | ref |  | ref |  |
Education | ||||
 Primary | 1.31 (1.02–1.70) |  | 1.20 (0.91–1.58) | 0.84 (0.33–2.13) |
 Secondary | ref |  | ref | ref |
 Higher education | 0.75 (0.64–0.88) |  | 0.75 (0.63–0.89) | 1.06 (0.55–2.05) |
Back pain | ||||
 LBP | 0.60 (0.49–0.72) | 0.70 (0.57–0.86) | 0.88 (0.71–1.09) | 0.60 (0.32–1.12) |
 NSP | 0.71 (0.61–0.84) | 0.70 (0.59–0.83) | 0.79 (0.66–0.95) | 0.81 (0.48–1.34) |
 LBP & NSP | ref | ref | ref | ref |
MDD/GAD | ||||
 No | 0.48 (0.41–0.56) | 0.49 (0.42–0.58) | 0.58 (0.48–0.69) | 0.44 (0.24–0.81) |
 Yes | ref | ref | ref | ref |
Self-rated health | ||||
 Excellent | 0.21 (0.16–0.29) | 0.23 (0.17–0.31) | 0.30 (0.22–0.43) | 0.30 (0.10–0.87) |
 Good | 0.28 (0.22–0.37) | 0.30 (0.23–0.39) | 0.38 (0.29–0.51) | 0.44 (0.18–1.09) |
 Moderate | 0.50 (0.38–0.64) | 0.50 (0.38–0.65) | 0.56 (0.42–0.75) | 0.65 (0.26–1.59) |
 Not good/Poor | ref | ref | ref | ref |
Health behaviours | ||||
 Physical activity |  |  |  |  |
 None/low | 1.09 (0.87–1.36) | 1.12 (0.89–1.41) |  | 1.40 (0.73–2.71) |
 Moderate | ref | ref |  | ref |
 High | 0.97 (0.79–1.18) | 1.00 (0.81–1.23) |  | 1.00 (0.52–1.94) |
 Vigourous | 0.72 (0.56–0.94) | 0.80 (0.60–1.05) |  | 0.50 (0.19–1.27) |
Regular analgesia | ||||
 No | 0.76 (0.66–0.88) | 0.82 (0.71–0.96) | 0.89 (0.76–1.05) | 0.60 (0.37–0.98) |
 Yes | ref | ref | ref |  |
 Missing |  |  |  |  |
Work variables | ||||
 Job demands 1–4 |  |  |  |  |
 First 4 years | 0.69 (0.58–0.81) | 0.69 (0.58–0.83) | 0.79 (0.66–0.95) | 0.86 (0.49–1.50) |
 After 4 years | 0.93 (0.77–1.12) | 0.90 (0.74–1.08) | 0.96 (0.78–1.17) | 1.12 (0.56–2.23) |
 Job control 1–4 | 0.82 (0.73–0.92) | 0.82 (0.72–0.94) | 0.85 (0.73–0.98) | 0.83 (0.53–1.28) |
 Job Support 1–4 |  |  |  |  |
 First 4 years | 0.72 (0.60–0.86) | 0.74 (0.61–0.89) | 1.00 (0.82–1.23) | 0.76 (0.41–1.38) |
 After 4 years | 1.01 (0.79–1.28) | 0.97 (0.76–1.24) | 1.22 (0.94–1.60) | 1.06 (0.47–2.36) |
 Low strain | 0.64 (0.50–0.82) | 0.62 (0.48–0.80) | 0.79 (0.61–1.03) | 1.02 (0.45–2.30) |
 Passive | 0.76 (0.59–0.98) | 0.75 (0.58–0.98) | 0.88 (0.68–1.16) | 1.07 (0.45–2.54) |
 Active | 0.78 (0.62–0.96) | 0.81 (0.64–1.02) | 0.94 (0.74–1.19) | 0.89 (0.43–1.82) |
 Strain | 0.88 (0.65–1.18) | 0.83 (0.61–1.13) | 0.98 (0.71–1.35) | 0.84 (0.32–2.21) |
 Iso-strain | ref | ref | ref | ref |