DEVELOPMENT OF THE REPERTORY GRID FOR MEASUREMENT OF INDIVIDUAL QUALITY-OF-LIFE IN CLINICAL-TRIALS

Current methods of studying quality of life (QoL) are usually based upon questionnaires and are unsatisfactory for several reasons, among which are the following: the items are derived from group studies, and are therefore insensitive to the manner in which individuals perceive and evaluate their personal QoL; the weights given to the items are also obtained from groups, to which the individuals under study do not even belong; the concepts to which the items relate are fixed a priori and do not allow possible changes during treatment or with the passage of time to be taken into account. This paper reports a first attempt to deal with these criticisms by applying the Repertory Grid (RG), a semi-structured interview technique originated by Kelly (1955), to the assessment of individual QoL. The method can also be used to measure therapeutic outcome in clinical trials, the main application of interest to drug companies, clinical pharmacologists and others. The development and initial validation of the RG for this purpose is described. The method is acceptable to patients, and gives quantifiable and interpretable individual results. Results from different QoL methods of assessing applied in a clinical trial are presented in the Appendix.