Measurement issues in health-related quality of life: Challenges for health psychology

Quality of life assessment is a central element of clinical trials and related forms of evaluative research. Early efforts to establish appropriate methods of measuring quality of life drew on psychometric principles and emphasised the need for validated measures. However, it is increasingly clear that, whilst still a central requirement of quality of life measures, validity needs to be emphasised alongside a number of other essential properties that have become clearer as the field has developed. Moreover formal psychometric methodology has to be adapted to take account of the specific needs of evaluative research. Research is beginning to develop more appropriate methods of outcome assessment in this area. Further lines of research are suggested to examine psychometric with other approaches to measurement of health-related quality of life.