QUALITY-OF-LIFE AND SOCIAL PRODUCTION-FUNCTIONS - A FRAMEWORK FOR UNDERSTANDING HEALTH-EFFECTS

Quality of life (QofL) has emerged as a new outcome paradigm. It is no w the endpoint in various taxonomies of patient outcomes, in which rel ationships are modeled amongst biological abnormalities, symptom statu s, functional status, disability, health perceptions and quality of li fe. Although current models and taxonomies point at important determin ants of QofL, they do not provide a heuristic that guides the conceptu alization of QofL and the systematic development of an explanatory the ory of how ill health affects QofL. General mechanisms linking ill hea lth, behavior, and QofL are lacking. In this paper we propose social p roduction function (SPF) theory as providing such a heuristic, relatin g the effects of ill health, the activities that patients engage in to maintain QofL, and QofL itself. This theory basically asserts that pe ople produce their own well-being by trying to optimize achievement of universal human goals via six instrumental goals within the environme ntal and Functional limitations they are facing. Three important notio ns of SPF theory are: (1) the linkages between goals, needs, and well- being; (2) the distinction between universal needs and instrumental go als; and (3) substitution among instrumental goals, activities and end owments according to cost-benefit considerations, whereby costs refer to scarce resources such as functional capacity, time, effort and mone y. We will argue that SPF theory meaningfully relates the ''biomedical model''-with its focus on pathological processes and biological, phys iological and clinical outcomes-to the ''quality of life'' model, with its focus on functioning and well-being We describe SPF theory and ho w SPF theory can be used to: (I) operationally define and measure QofL ; (2) clarify persistent measurement problems; and (3) develop an expl anatory framework of the effects of disease on QofL. In the discussion section, we address the limitations of the SPF approach of QofL and i ts relationship with personality. (C) 1997 Elsevier Science Ltd.