METHODOLOGIC ASSESSMENTS OF QUALITY-OF-LIFE MEASURES IN CLINICAL-TRIALS

OBJECTIVE: To provide a comprehensive overview and to evaluate the qua lity of published clinical trials assessing the effect of drug therapy on patients' quality of life. DATA SOURCE: Clinical trials that asses sed the effect of drug therapy on patient quality of life published in English, peer-reviewed journals were identified through a MEDLINE sea rch (1966-1995) and review of references from recent publications. DAT A EXTRACTION: A data collection form was used to record information on trial demographics, quality-of-life assessment, study design, and sta tistical analyses. A quality score was computed for each article based on a checklist of items. RESULTS: Two hundred sixty-five articles wer e eligible for this study. Reliability data on the quality-of-life ins truments were provided by 23.8% of the studies and validity data were provided by 21.5%. Quality of life was defined in about 14% of the tri als, while 15% provided the rationale for selecting the specific instr ument(s). The average overall quality score for the trials was 0.34, b ased on a scale of 0-1. The trials with quality-of-life scores as the primary end point had significantly higher quality scores than those d esigned primarily to measure clinical outcomes (p < 0.05). CONCLUSIONS : Although there was a gradual but significant improvement in the qual ity of published clinical trials over time, more attention should be p aid to various aspects of quality-of-life assessment (e.g., defining c onstruct, instrument selection).