Personal risk factors that were analysed
| Variable | Classification |
| Demographic | |
| Sex | Male (n=2935); female (n=5675) |
| Age at baseline (years) | 20–29 (n=1944); 30–39 (n=2777); 40–49 (n=2499); 50–59 (n=1390) |
| Lifestyle | |
| Smoking | Never (n=5555); ex-smoker (n=1201); current (n=1831); not known (n=23) |
| Psychological | |
| Mental health | Good (n=3414); intermediate (n=2603); poor (n=2562); not known (n=31) |
| No of distressing somatic symptoms | 0 (n=5138); 1 (n=1894); ≥2 (n=1532); not known (n=46) |
| Adverse health beliefs about low back pain* | |
| Work-relatedness | No (n=5628); yes (n=2982) |
| Physical activity | No (n=6949); yes (n=1661) |
| Prognosis | No (n=7402); yes (n=1208) |
| Adverse health beliefs about arm/shoulder/hand pain†‡§ | |
| Work-relatedness | No (n=5989); yes (n=2621) |
| Physical activity | No (n=7543); yes (n=1067) |
| Prognosis | No (n=7722); yes (n=888) |
| Occupational activities in an average working day | |
| Lift weights of 25 kg or more by hand*†‡ | No (n=5510); yes (n=3100) |
| Work for >1 hour in total with hands above shoulder height†‡ | No (n=5812); yes (n=2798) |
| Use of keyboard or typewriter for >4 hours in total†‡§ | No (n=5496); yes (n=3114) |
| Other tasks involving repeated movements of the wrist or fingers for >4 hours in total§ | No (n=3230); yes (n=5380) |
| Psychosocial aspects of work | |
| Work >50 hours per week | No (n=6670); yes (n=1940) |
| Time pressure | No (n=2181); yes (n=6429) |
| Incentives | No (n=6230); yes (n=2380) |
| Lack of support | No (n=6359); yes (n=2251) |
| Job dissatisfaction | No (n=6950); yes (n=1660) |
| Lack of control | No (n=6878); yes (n=1732) |
| Job insecurity | No (n=6074); yes (n=2536) |
| Previous sickness absence | |
| Absence for >5 days in total in year before baseline for non-musculoskeletal problems | No (n=7841); yes (n=769) |
| Pain propensity | |
| Pain propensity index¶ | 0; 1; 2; 3; 4; 5; ≥6 (numbers varied by outcome) |
*Analyses of sickness absence for low back pain.
†Analyses of sickness absence for neck pain.
‡Analyses of sickness absence for shoulder pain.
§Analyses of sickness absence for wrist/hand pain.
¶For each outcome, pain propensity index was defined according to the number of anatomical sites, excluding the outcome site, that had been painful in the year before baseline (see text).