Validity and Responsiveness of the Work Functioning Impairment Scale in Workers With Depression.

Abstract

We aimed to evaluate the convergent validity and responsiveness of the work functioning impairment scale (WFun) in patients with depression, a major disease causing presenteeism. Baseline testing was performed using WFun, the Quick Inventory of Depressive Symptomatology (QIDS), 17-item Hamilton Depression Rating Scale (HAM-D), and Montgomery-Asberg Depression Rating Scale (MADRS) in 37 outpatients with major depression or bipolar disorder who were working. The QIDS and WFun scores were measured several times for responsiveness evaluation. Regression analyses showed significant positive correlations between baseline WFun and HAM-D and MADRS scores. Changes in WFun and QIDS scores were positively correlated for QIDS scores. Our results suggest that WFun is convergently valid and responsive for determining the clinical severity of depression in workers treated as psychiatric outpatients.