Multivariate logistic regression models to predict clinically relevant psychological distress (GHQ-12 ≥ 3) at T1, T2, T3 and all timepoints.

Models were selected through stepwise forwards and backwards regression to obtain the lowest Akaike Information Criterion (AIC). In the final mixed effects model, participant ID was included as a random effect. OR: odds ratio. 95% CI: 95% confidence interval. AIC: Akaike Information Criterion. ROC: receiver operating curve. ICC: intraclass correlation coefficient. For weekly hospital shifts, the OR is the increase in risk per additional shift worked.