Objectives The aim of the study was to investigate association between work ability and return to work (RTW) with special focus on workplace rehabilitation in combination with supportive conditions at work.

Methods Questionnaire data from a cohort of women (n=324) working within Human Service Organization, on long-term sick leave (>60 days) were used (baseline, 6 months and 12 months). To investigate the importance of interactive conditions of workplace rehabilitation and supportive conditions on the effect of work ability and RTW, one-way analysis of variance (ANOVA) was used.

Results Work ability index increased significantly more at 12 month in the group that had workplace rehabilitation and supportive conditions such as influence at work (diff=7, 95% CI (2 to 12)), degree of freedom at work (diff=5, 95% CI (0 to 10) and work satisfaction (diff=9, 95% CI (4 to 15)), than the group that had workplace rehabilitation and no supportive conditions. Results were similar for single-item on work ability, additionally significant for increased work ability index among the group that had workplace rehabilitation and possibilities for development at work (diff=2, 95% CI (0 to 5). Working degree increased significantly more at 12 month in the group that had workplace rehabilitation and supportive conditions such as sense of feeling welcomed (diff=24, 95% CI (2 to 46), influence (diff=24, 95% CI (3 to 44), and satisfaction at work (diff=28, 95% CI (4 to 52), compared to workplace rehabilitation and no supportive conditions.

Conclusions The results in this study suggest the importance of integrating workplace rehabilitation with supportive conditions at work to increase work ability and improve the RTW process for women being on long term sick leave.