Abstract: We included nine studies reporting on 10 psychological interventions and one combined intervention. The studies included 1546 participants. No RCTs were found of pharmacological interventions, exercise programmes or employee assistance programmes. We assessed seven studies as having low risk of bias and the studies that were pooled together were comparable. For those who received no treatment, compared with CBT, the assumed time to partial and full RTW was 88 and 252 days respectively. Based on two studies with a total of 159 participants, moderate-quality evidence showed that CBT had similar results for time (measured in days) until partial RTW compared to no treatment at one-year follow-up (mean difference (MD) -8.78, 95% confidence interval (CI) -23.26 to 5.71). We found low-quality evidence of similar results for CBT and no treatment on the reduction of days until full RTW at one-year follow-up (MD -35.73, 95% CI -113.15 to 41.69) (one study with 105 participants included in the analysis). Based on moderate-quality evidence, problem solving therapy (PST) significantly reduced time until partial RTW at one-year follow-up compared to non-guideline based care (MD -17.00, 95% CI -26.48 to -7.52) (one study with 192 participants clustered among 33 treatment providers included in the analysis), but we found moderate-quality evidence of no significant effect on reducing days until full RTW at one-year follow-up (MD -17.73, 95% CI -37.35 to 1.90) (two studies with 342 participants included in the analysis). We found moderate-quality evidence that CBT did not significantly reduce time until partial RTW and low-quality evidence that it did not significantly reduce time to full RTW compared with no treatment. Moderate-quality evidence showed that PST significantly enhanced partial RTW at one-year follow-up compared to non-guideline based care but did not significantly enhance time to full RTW at one-year follow-up. An important limitation was the small number of studies included in the meta-analyses and the small number of participants, which lowered the power of the analyses.

Plain-language summary: Our study assessed how effective these treatments are at enabling the sick-listed worker to return to partial or full-time work. We searched databases containing articles from different scientific journals and looked for studies that tested whether a certain type of treatment helped the worker to return to work when on sick leave because of an adjustment disorder. We found nine relevant studies. In total, 10 psychological treatments were evaluated and one combined treatment consisting of a psychological treatment and relaxation techniques. We found no studies on pharmacological interventions, exercise programmes or employee assistance programmes. The nine studies included in this review reported in total on 1546 participants. Of the 10 psychological treatments, five consisted of cognitive behavioural therapy and five of problem solving therapy, which are commonly used types of treatment for patients with mental health problems. Our results showed that workers on sick leave because of an adjustment disorder can be helped with making their first step back to work (i.e. partial return to work) by treating them with problem solving therapy. On average, workers who are offered problem solving therapy start 17 days earlier with partial return to work compared to workers who receive no treatment or the usual treatment from their occupational physician or general practitioner. However, we also found that cognitive behavioural therapy or problem solving therapy does not help the worker return to work with full-time hours any quicker than workers who receive no treatment or the usual treatment from their occupational physicians or general practitioners. These results are based on moderate-quality evidence, which implies that further research is likely to have an important impact on our confidence in the results and may change the results.