International development of the Quality of Life in Depression Scale (QLDS).

Author: McKenna, S. P., Doward, L. C., Kohlmann, T., Mercier, C., Niero, M., Paes, M., Patrick, D., Ramirez, N., Thorsen, H., Whalley, D.

Source:
Journal of Affective Disorders. 63(1-3), Mar 2001, 189-199.
The Quality of Life in Depression Scale (QLDS) employs the needs-based model of quality of life (QoL) and was developed in the UK and The Netherlands as an outcome measure for clinical trials. This paper describes the production and psychometric assessment of nine new language versions for Canada (French and English), Denmark, France, Germany, Italy, Morocco, Spain and the US. Methods: Three adaptation stages were employed; production of conceptually equivalent translations, field-test interviews and assessment of reliability and construct validity by survey of patients with major depression. Few problems were experienced with producing conceptually equivalent translations, except in Morocco. Patients in the field-test interviews found the instrument to have appropriate content and to be easy to complete. Internal consistency and test-retest reliability were excellent for all language versions and scores were found to relate appropriately to measures of depression severity and health status.