Self-report quality of life measure for people with schizophrenia: The SQLS

Abstract

Background: Quality of life is the subject of growing interest and investigation. Aims: To develop and validate a short, self-report quality of life questionnaire (the Schizophrenia Quality of Life Scale, SQLS). Method: People with schizophrenia in Liverpool were recruited via the NHS. Items, generated from in-depth interviews, were developed into an 80-item self- report questionnaire. Data were factor analysed, and a shorter form measure was tested for reliability and validity. This measure was administered together with other self-report measures -SF-36, GHQ-12 and HADS - to assess validity. Results: Data were analysed to produce a final 30-item questionnaire, comprising three scales ('psychosocial', 'motivation and energy', and 'symptoms and side-effects') addressing different SQLS dimensions. Internal consistency reliability of the scale was found to be satisfactory. There was a high level of association with relevant SF-36, GHQ- 12 and HADS scores. Conclusions: The SQLS was completed within 5-10 minutes. It possesses internal reliability and construct validity, and promises to be a useful tool for the evaluation of new treatment regimes for people with schizophrenia. Declaration of interest: Janssen-Cilag Ltd funded the project. G.W. is Editor of The British Journal of Psychiatry.