References
- Fitzpatrick R, Fletcher A, Gore S. Quality of Life measures in health care. I: Applications and issues in assessment. Br Med J 1992; 305: 1074–7
- Fletcher A, Gore S, Jones D. Quality of Life measures in health care. II: Design, analysis and interpretation. Br Med J 1992; 305: 1145
- Guyatt G H, Walter S, Norman G. Measuring change over time: assessing the usefulness of evaluative instruments. J Chron Dis 1987; 40: 171–8