Quality of life in depression scale (QLDS). Development, reliability, validity, responsiveness and application

The joint development of the Dutch and English versions of the Quality of Life in Depression Scale (QLDS) is described. The QLDS is based on the needs model of quality of life developed by Hunt and McKenna. The scale has good reliability and internal consistency. Test-retest correlation coefficients were 0.94 and 0.87 in the United Kingdom and the Netherlands, respectively. Internal consistency alpha-coefficients were 0.95 and 0.92, respectively. The validity of the scale is highly acceptable. The QLDS was shown to correlate relatively highly with established measures of well-being, and scores obtained with the measure were related to severity of depression as assessed by the Hamilton Rating Scale for Depression. The QLDS was shown to be responsive to change in an open study with fluoxetine in 540 patients with major depression. The scale has wide applicability and has been shown to be user-friendly, both for respondents and administrators. It has been, or is in the process of being, tested for reliability and validity in the following additional countries: Australia, Austria, Belgium, Canada, Denmark, France, Germany, Italy, Morocco, Spain and the United States.