Association between different combinations of poor work ability* and sleep disturbances†, and long-duration activity limiting neck and/or back pain
| Cases/all | Crude RR | 95% CI | Adjusted‡ RR | 95% CI | |
| Good work ability/no sleep disturbances | 534/7281 | ref | ref | ||
| Poor work ability/no sleep disturbances | 91/552 | 2.4 | 2.0 to 3.0 | 2.1 | 1.7 to 2.6 |
| Good work ability/sleep disturbances | 294/2610 | 1.5 | 1.3 to 1.8 | 1.5 | 1.3 to 1.7 |
| Poor work ability/sleep disturbances | 117/647 | 2.4 | 1.9 to 2.9 | 2.1 | 1.6 to 2.6 |
*Assessed with WAI (Work Ability Index) items, self-perceived physical and/or mental work ability in relation to job demands and defined as moderate, rather poor, poor.
†Sleep disturbances=current mild or severe sleep disturbances.
‡Adjusted for socioeconomic status, long-standing illness and subsample (years 2002, 2006, 2010)
RR, risk ratio.