PT - JOURNAL ARTICLE AU - G. H. Guyatt AU - C. Bombardier AU - P. X. Tugwell TI - Measuring disease-specific quality of life in clinical trials DP - 1986 Apr 15 TA - Canadian Medical Association Journal PG - 889--895 VI - 134 IP - 8 4099 - http://www.cmaj.ca/content/134/8/889.short 4100 - http://www.cmaj.ca/content/134/8/889.full SO - CMAJ1986 Apr 15; 134 AB - While measurement of quality of life is a vital part of assessing the effect of treatment in many clinical trials, a measure that is responsive to clinically important change is often unavailable. Investigators are therefore faced with the challenge of constructing an index for a specific condition or even for a single trial. There are several stages in the development and testing of a quality-of-life measure: selecting an initial item pool, choosing the "best" items from that pool, deciding on questionnaire format, pretesting the instrument, and demonstrating the responsiveness and validity of the instrument. At each stage the investigator must choose between a rigorous, time-consuming approach to questionnaire construction that will establish the clinical relevance, responsiveness and validity of the instrument and a more efficient, less costly strategy that leaves reproducibility, responsiveness and validity untested. This article describes these options and outlines a pragmatic approach that yields consistently satisfactory disease-specific measures of quality of life.