Occupational Functioning Scale (OFS)--an instrument for assessment of work ability in psychiatric disorders.

The aim was to present the content of the newly developed observer rating scale of work ability--The Occupational Functioning Scale (OFS)--and its basic psychometric properties. Psychiatric disorders cause functional impairment in several domains, including occupational functioning. The assessment of work-related functioning is often neglected in psychiatric research, partly due to a lack of reliable and valid instruments.