Letters Defining and Measuring Quality of Life in Medicine To the Editor.—Drs Leple ´ ge and Hunt 1 assert that variability across cultures, between patients, and in the same patient over time makes efforts to define the term quality of life im- possible. It is an “idiosyncratic mystery.” They conclude that physicians and health economists should avoid quality of life assessment. At the same time, the authors assert that quality of life is paramount to patients and is, indeed, the only concern of the patient who seeks medical care. The unwelcome conclu- sion is that outcomes—whether patients feel better and are able to do more, whether they are spared subsequent treat- ments, and whether they are glad they sought medical care— are not a part of medicine. This argument, however, rests on a faulty assumption. Vari- ability among patient appraisal of quality of life is limited. No one thinks severe abdominal pain is better than a runny nose, as Fanshel and Bush 2 long ago pointed out (even if it is difficult, as they recognized, to find a measurement unit that expresses their relative quality-of-life impact). Even cultural variation has limits. When asked about their ability to carry out common tasks of daily living, the responses of !Kung and Herero elders of southwest Africa (seminomadic pastoralists) were best un- derstood in terms of a physical function component highly correlated with age. 3 More generally, utilities elicited for health states are highly correlated across populations and across sociodemographic groups. 4 If health state utilities do vary according to patient health status (as demonstrated for dialysis patients 5 but not, however, for all patient groups), this variability only shows that other distinct features of patient experience must be considered by clinicians when recommend- ing treatments or assessing outcomes. These include family support systems, willingness to adopt prosthetic technologies, and patient attachment to life. Leple ´ ge and Hunt have exaggerated the idiosyncratic na- ture of health-related quality of life (HRQL) by confounding it with quality of life more generally. This distinction is critical: HRQL measures are likely to be more highly correlated with health status and more sensitive to changes in health than general quality-of-life measures. When the authors suggest that quality of life be viewed as “the best possible physical and emotional state compatible with [a patient’s] medical condi- tion,” they are talking about HRQL, which is already well assessed by a variety of measurement tools. When they com- plain that such measures of health status do not capture other components of patient quality of life, such as the capacity to love or have “a positive approach to everyday events,” they are right, but the measures also were never intended to do so. Steven M. Albert, PhD, MSc Columbia University New York, NY 1. Leple ´ ge A, Hunt S. The problem of quality of life in medicine. JAMA. 1997;278:47-50. 2. Fanshel S, Bush JW. A health status index and its application to health services outcomes. Operations Res. 1970:1021-1066. 3. Draper P, Harpending H. Work and aging in two African societies: !Kung and Her- ero. In: Bonder BR, ed. Occupational Performance in the Elderly. Philadelphia, Pa: FA Davis Co Publishers; 1994. 4. Patrick DL, Sittampalam Y, Somerville SN, et al. A cross-cultural comparison of health status values. Am J Public Health. 1985;75:1402-1407. 5. Sackett DL, Torrance GW. The utility of different health states as perceived by the general public. J Chronic Dis. 1978;31:697-704. To the Editor.—Drs Leple ´ ge and Hunt 1 provide an incomplete view of the current state of the science of HRQL measure- ment. We disagree with their pessimism about the value of aggregated and normative outcome measures. Health out- comes researchers must specify the conceptual model under- lying an instrument; the patients’ perspective is critical in the development of HRQL measures. We agree that patients are the main source for information about the content and impor- tance of domains to ensure that a quality-of-life measure ad- equately reflects the impact of disease on functioning in ev- eryday life and well-being. Most current instruments start with eliciting concerns from patients (by qualitative methods or focus groups) to determine the relevant domains. Problems with confusing and unclear terminology have con- tinued in HRQL research. The use of “subjective health sta- tus” rather than “quality of life” will not resolve the problems the authors have raised. We use HRQL when addressing qual- ity-of-life outcomes that can be affected directly by health care interventions, a stance consistent with Wilson and Cleary, 2 reserving quality of life for the global appraisal of life quality. Patient outcomes describe the full range of measures used in health evaluation, including clinical measures, symptoms, functioning, and well-being. Cultural differences present another challenge to HRQL assessment. Studies have demonstrated that important do- mains, such as physical, social, and psychological well-being, are consistent across cultures. It is the expression of these domains, including the range of activities and behaviors, that varies within and between cultures and countries. The chal- lenge is to design instruments to assess HRQL in culturally meaningful ways and apply scientifically based methods for linguistic and cultural validation. Patients’ adaptation to and acceptance of their disease state can lead to the apparent discordant finding that normative health status measures demonstrate severe functional limita- tions, while subjective ratings reflect patients’ satisfaction with the quality of their life. Both perspectives are important in evaluating the impact of health interventions. Idiographic measures are useful for understanding the characteristics that drive individuals’ assessments of their quality of life. Stan- dardized, normative measures are useful for making compari- sons of health care interventions and different populations. Applications of techniques, such as 3-mode factor analysis, 3 that combine the normative and idiographic approaches can be used to further understand responses to assessment in- struments. Methodological advances in health outcomes assessment over the past 30 years have facilitated the introduction of pa- tient outcomes in clinical trials, the monitoring of the health Edited by Margaret A. Winker, MD, Senior Editor, and Phil B. Fontanarosa, MD, Senior Editor. Guidelines for Letters Letters will be published at the discretion of the editors as space per- mits and are subject to editing and abridgment. Letters will be considered if they are typewritten double-spaced and do not exceed 500 words of text and 5 references. Please include a word count. Letters discussing a recent JAMA article should be received within 4 weeks of the article’s publication. Letters must not duplicate other material published or submitted for publication. A signed state- ment for authorship criteria and responsibility, financial disclosure, copyright transfer, and acknowledgment is essential for publica- tion. Letters not meeting these specifications are generally not considered. Letters will not be returned unless specifically requested. Also see JAMA Instructions for Authors (January 7, 1998). Letters may be submitted by surface mail: Letters Editor, JAMA, 515 N State St, Chicago, IL 60610; e-mail: JAMA-letters@ama-assn.org; or fax (please also send a hard copy via surface mail): (312) 464-5824. JAMA, February 11, 1998—Vol 279, No. 6 Letters 429 ©1998 American Medical Association. All rights reserved. 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