Validation of the Recovering Quality of Life (ReQoL) questionnaires for patients with anxiety, obsessive-compulsive, stress-related, somatoform and personality disorders in Germany

The health-related quality of life (HrQoL) and the recovery process of persons with mental health conditions can be assessed with the Recovering Quality of Life questionnaires (ReQoL-20 and ReQoL-10). The aim of this study was to assess the psychometric properties of the German version of the ReQoL measures in patients with anxiety, obsessive-compulsive, stress-related, and somatoform disorders and in patients with disorders of adult personality and behavior. This study was based on a sub-sample of patients that were included in a randomized controlled trial evaluating an evidence-based, stepped and coordinated care service model for mental disorders (RECOVER). The internal consistency was assessed using Cronbach's Alpha and the test-retest reliability was assessed by the intra-class correlation coefficient (ICC). Concurrent validity was assessed by Pearson's Correlation Coefficient and the known-group validity was assessed using the Cohen's d. The internal consistency of the ReQoL-20 and ReQoL-10 was excellent and good with Cronbach's alpha of α = 0.91 and α = 0.83 for all items. The test-retest reliability of the ReQoL measures was moderate with ICC of r = 0.72 to 0.74. The concurrent validity of the ReQoL measures with the Global Severity Index was overall high with a correlation coefficient of r = -0.70. In conclusion, for patients with anxiety, obsessive-compulsive, stress-related, somatoform and personality disorders, the German version of the ReQoL measures is valid and reliable for the assessment of HrQoL and the recovery process.