Table 5 Multivariate model: predictors of knee pain onset.

	Relative risk* (95% CI)
Lift or carry weights in one hand (if yes, weight split at median†)
None		1.0
<20 lbs		2.1 (1.3 to 3.2)
>20 lbs		1.7 (1.03 to 2.8)
General psychological distress (GHQ—tertiles)
Low		1.0
Medium		1.5 (0.9 to 2.3)
High		1.6 (1.02 to 2.6)

GHQ, general health questionnaire.

The median value of weights differed at t₀ and t₁. Weights split at the median at t₀ and at this value at t₁.

*Adjusted for age, sex, occupational group, height, weight, body mass index and physical activity;

†Exposures recorded for “last working day”.