Conceptualisation and Measurement of Quality of Life Based on Schalock and Verdugo's Model: A Cross-Disciplinary Review of the Literature

Researchers in the medical and social sciences have shown a rapidly growing interest in the concept of Quality of Life (QoL) in the past few decades. Reasons include its potential as an outcome measure of service delivery, and the opportunity of using a shared language both within and between different disciplines. Despite the widespread use of QoL in research, practice and policy development, there is little agreement on the defining aspects, as well as on the operationalization of the concept. In an attempt to broaden the knowledge on QoL and to give an overview of interdisciplinary consensus- and discussion aspects, a review of peer-reviewed QoL-reviews, indexed in Web of Science, and published from 2000 to 2013 (n = 75) was carried out. Theoretical and measurement principles, derived from the QoL-framework of Schalock and Verdugo (Handbook on quality of life for human service practitioners, American Association on Mental Retardation, Washington, 2002) were systematically explored. Results indicate a growing interdisciplinary consensus on QoL as (1) a multidimensional construct, (2) composed of both objective and subjective dimensions, (3) with an emphasis on the subjective evaluation of one's life circumstances, (4) which is dynamic in nature and (5) which can be influenced and enhanced by a variety of factors, implying a positive view on social services. Contrary, debate is still going on (1) the ideal method to assess QoL, (2) the use of proxies in QoL-measurement and (3) the preference for a general or on the contrary disease- or target group specific QoL-instrument.