Jolanda De Vries and Guus L.Van Heck WHO Quality of Life Assessment Instrument The World Health Organization Quality of Life Assessment Instrument (WHOQOL-100): Validation Study with the Dutch Version Jolanda De Vries and Guus L. Van Heck Department of Psychology, Tilburg University, Tilburg, The Netherlands In this study, we examine the reliability and validity of a new quality-of-life (QoL) instrument, the Field Trial Version of the World Health Organization Quality of Life assessment instrument (WHOQOL-100). Two- hundred-and-twenty persons, 147 healthy individuals, and 73 chronic fatigue syndrome (CFS) patients completed the WHOQOL-100 and a test battery of related measures. The WHOOQL-100 has a fairly good internal consistency and a good validity. Keywords: Quality of life, psychometrics, assessment, health, self-esteem Introduction Practically all psychological research into quality of life (QoL) is related to health. Health-related QoL is a topic with a growing popularity in health psy- chology. In 1985, De Haes and Van Knippenberg noted that health-related QoL has not been defined explicitly. Today this remark still generally holds. Grieco and Long (1984) conceived of QoL as re- flecting impairment in functional performance. In 1985, Kaplan used the term “quality of life” to de- scribe the impact of disease and disability upon dai- ly functioning. In another definition, health-related QoL has been defined as “the end result of an adap- tive process that begins with uncertainty in illness, continues through appraisal of uncertainty as dan- ger or opportunity, and incorporates coping strate- gies to manipulate the uncertainty in the desired di- rection” (Padilla, Mishel, & Grant, 1992, p. 156). Fi- nally, Patrick and Erickson (1993, p. 20) defined health-related QoL as “the value assigned to dura- tion of life as modified by the impairments,function- al states, perceptions, and social opportunities that are influenced by disease, injury, treatment, or poli- cy.” The current popularity of QoL arises from the fact that health-related QoL is increasingly being recognized as an important outcome measure of medical treatment, and as a supplement to tradi- tional biological end-points such as mortality (Hays & Shapiro, 1992). Information concerning health- related QoL can add to medical knowledge ob- tained, for instance, in the context of clinical trials (Moinpoir et al., 1989). Although often the term “health-related QoL” is used, studies in this area usually focus on illness and the impact it has on health and functional status (Bergner, 1985). In addition, while most authors claim that their instrument assesses health-related QoL, most measures are, strictly speaking, predom- inantly health-status measures that focus on the in- fluence of disease on physical functioning (e. g., Ber- gner, 1985; Stoker, Dunbar & Beaumont, 1992). One problem that occurs when studying QoL with health status measures is that lower levels of functioning are equated with lower QoL. This con- trasts sharply with empirical findings reflecting high perceived QoL in spite of low levels of functioning. Furthermore, QoL has a much wider scope than health status. For instance, it contains more domains than current health status measures. Moreover, QoL encompasses the respondents’ own perception of aspects of their life, while health status asks respon- dents about behavior. An example of a subjective QoL question is “How satisfied are you with the support you get from your family?”, whereas an ex- ample of a health status statement is “I isolate my- self as much as I can from the rest of the family.” In most of the health-status studies the emphasis is typically placed on the measurement of control of symptoms specific to the disease process (e. g., angi- na in cardiac disease), physical functional status, and work status (Burckhardt, Woods, Schultz, & Zie- barth, 1989). European Journal of Psychological Assessment, Vol. 13, Issue 3, pp. 164–178 © 1997 Hogrefe & Huber Publishers ${protocol}://econtent.hogrefe.com/doi/pdf/10.1027/1015-5759.13.3.164 - Tuesday, August 21, 2018 8:30:49 PM - Technische Universität München IP Address:129.187.254.46