[The evaluation of the quality of life in asthma patients. Value and implementation]

Asthma, as a chronic condition, alters individual's day-to-day life in functional, emotional and social domains. There has been a recent upsurge of interest in the assessment of quality of life in asthmatic patients. Indeed, there is growing evidence that conventional outcomes of asthma (symptoms assessments, functional measures...) although important, may not detect all the changes experienced by patients. Quality-of-life instruments target two distinct properties. First, discriminative instruments are needed to distinguish between individuals or groups of patients. Second, an evaluative instrument is required to detect such changes in an individual or group of patients, as occur in clinical trials. There are now a number of quality-of-life instruments, with strong measurement properties, that can be used in clinical trials.