Background. Major depression has far-reaching consequences for work functioning and absenteeism. In most cases depression is treated by medication and clinical management. The addition of occupational therapy (OT) might improve outcome. We determined the cost-effectiveness of the addition of OT to treatment as usual (TAU).

Method. Sixty-two adults with major depression and a mean absenteeism of 242 days were randomized to TAU (out-patient psychiatric treatment) or TAU+OT [6 months, including (i) diagnostic phase with occupational history and work reintegration plan, and (ii) therapeutic phase with individual sessions and group sessions]. Main outcome domains were depression, work resumption, work stress and costs. Assessments were at baseline and at 3, 6, 12 and 42 months.

Results. The addition of OT to TAU: (i) did not improve depression outcome, (ii) resulted in a reduction in work-loss days during the first 18 months, (iii) did not increase work stress, and (iv) had a 75·5% probability of being more cost-effective than TAU alone.

Conclusion. Addition of OT to good clinical practice does not improve depression outcome, improves productivity without increasing work stress and is superior to TAU in terms of cost-effectiveness.