Objectives Workers with common mental disorders (CMDs) frequently experience recurrent sickness absence, but interventions are lacking to prevent a recurrence. The aim of this study was to evaluate the effectiveness of the SHARP-at work intervention in preventing recurrent sickness absence among workers who returned to work after sickness absence due to CMDs.

Methods We performed a cluster-randomised controlled parallel-group trial with follow-up at 3, 6 and 12 months. Occupational physicians were randomised to either a 3-day training in the SHARP-at work intervention, a problem solving intervention, or usual care. Primary outcome measures were the incidence of recurrent sickness absence and time to recurrent sickness absence.

Results 80 participants were randomised in the intervention group and 78 in the control group. The adjusted odds ratio for the incidence of recurrent sickness absence was 0.40 (95% confidence interval (CI) 0.20 to 0.81) and the adjusted hazard ratio for time to recurrent sickness absence was 0.53 (95% CI 0.33 to 0.86) for the intervention group compared to CAU.

Conclusions This study demonstrates the 12-month effectiveness of a problem solving intervention for reducing recurrent sickness absence in workers with CMDs and stresses the importance of continuous attention of health care providers for workers who have been on sickness absence due to CMDs.