[The concept of quality of life in medicine: its history and current relevance].

This paper attempts to review 40 years of quality-of-life research. The increasing recognition of the topic is obvious from the number of publications and its representation in academic discussions. Despite a rather weak theoretical foundation, methods of quality-of-life assessment have been developed successfully. Both the number and the quality of assessment tools have increased over the years so that there is now a broad spectrum of instruments for adults and children available, which is used from epidemiological studies to health services research, and especially in quality assurance and comparative benchmarking. Assessment is still underrepresented in clinical trials, which is why only few meta-analyses and reviews are available. Also, implementation of results in recommendations for treatment and in guidelines has just started. Implications for clinical practice also relate to the patient orientation in the physician-patient communication. A future perspective is the widespread use of available instruments, provided that relevant information is gained, which depends on the study design as well as the interpretation and dissemination of results. Consequences for the healthcare systems are expected if improvements in quality of life can be attributed to benefits of treatment and surrounding services.