Measurement accuracy in assessing patient’s quality of life: to weight or not to weight domains of quality of life Errol J. Philip Æ Thomas V. Merluzzi Æ Amy Peterman Æ Lisa B. Cronk Accepted: 16 May 2009 / Published online: 4 June 2009 Ó Springer Science+Business Media B.V. 2009 Abstract Purpose Health-related quality of life (HRQOL) mea- sures typically do not incorporate patients’ preferences for domains such as physical, emotional, functional and social/ family well-being, which may compromise precision. Method A forced-choice domain-preference measure was developed to assess the importance of HRQOL domains. About 194 cancer patients completed the domain-prefer- ence measure, along with measures of HRQOL, coping, adjustment, and life satisfaction. Results Patients ranked emotional well-being as most important and the loss of social-family well-being as the most difficult to do without. A weighting algorithm revealed no advantage to incorporating individuals’ domain preferences in HRQOL assessment; however, preliminary evidence suggested that HRQOL measurement may be more accurate in predicting outcomes for individ- uals with no distinct domain preferences than those with distinct preference profiles. Conclusion This study provides preliminary evidence for the validity of current measures of HRQOL, which may inherently take into account patients’ domain preferences. Keywords Quality of life Á Cancer Á Domain-preference Introduction Advancements in medical treatment have substantially increased the number of people living with cancer [1]. It is estimated that over 1.4 million people will be diagnosed with this disease in 2009 alone, joining the estimated 10 million who are currently living with a diagnosis in the United States [2]. These estimates have brought the long- term management of cancer to the forefront of the health care agenda [1]. They have also prompted increasing attention to the accurate assessment of patient-reported treatment outcomes [3, 4]. One such outcome that has received considerable attention is health-related quality of life (HRQOL) [4, 5]. The assessment of individuals’ HRQOL incorporates their appraisal of both the effects of their clinical diagnosis, as well as treatment side-effects, and can provide important information in optimizing medical treatment [4, 6–9]. Accurate HRQOL assessment can therefore assist in making patients’ priorities explicit to both patients them- selves and their health professionals, and can represent an important factor in guiding care decisions. Current mea- sures evaluate patients’ HRQOL across a number of domains; however, they do not explicitly evaluate patients’ priorities or preferences, and thus may be unable to pre- cisely identify priorities in care. Further, patients’ HRQOL domain preferences may change over time depending on treatment progression and life situation, as well as differ as a function of demographic and disease characteristics. The ability to more precisely and efficiently assess patients’ HRQOL in a clinical setting is therefore critical in pro- viding comprehensive and individually tailored medical E. J. Philip (&) Department of Psychology, University of Notre Dame, Notre Dame, IN 46556, USA e-mail: ephilip@nd.edu T. V. Merluzzi University of Notre Dame, Notre Dame, IN, USA A. Peterman University of North Carolina, Charlotte, NC, USA L. B. Cronk Mayo Clinic, Rochester, MN, USA 123 Qual Life Res (2009) 18:775–782 DOI 10.1007/s11136-009-9492-0