A brief history of the Quality of Life: its use in medicine and in philosophy.

The term Quality of Life (QoL) has been increasingly used in medical and philosophical literatures for the past four decades. The purpose of this article is to analyze how QoL is being used in medicine and in philosophy to understand its current status. In the 1960s and 1970s new technologies raised new questions for clinicians, so they used QoL as a parameter for making decisions in health issues. Consequently, researchers focused their interest on the construction and testing of instruments designed to measure health and QoL. However, all these instruments showed some conceptual and methodological problems that made the use of QoL in medicine difficult. While some researchers considered QoL an "idiosyncratic mystery", others believed that QoL was useful in implementing the patient's point of view into clinical practice and they suggested improving QoL's definition and methodology. In the 1980s, some consequentialist philosophers used QoL to formulate moral judgment, in particular they justified infanticide for some severely handicapped infants, and both euthanasia and suspension of life-sustaining treatment using QoL. In the 1990s, welfarist philosophers opened a new debate about QoL and they associated it with health and happiness. These philosophers developed QoL and those other concepts as subjectivist notions; consequently their definition and their measurements pose challenges. Afterwards researchers' interest in theoretical issues regarding QoL has fallen; nevertheless, physicians have continued to use QoL in clinical practice.