MEASURES OF LIFE QUALITY, ROLE PERFORMANCE, AND FUNCTIONAL STATUS IN ASTHMA RESEARCH

Recently a consensus has emerged that health care research should addr ess outcomes important to patients, especially quality of life, role p erformance, and functional status. The assessment of such outcomes is beset by conceptual and methodological difficulties that may be especi ally problematic for asthma. Nevertheless, several broad conclusions m ay be drawn about the use of measures of these outcomes in asthma rese arch. Asthma usually is reasonably well controlled if patients are mod erately adherent to their recommended regimens. Consequently, the bene ficial impacts of interventions are likely to be small, and large samp les are required to detect them. Outcome assessment should combine ast hma-specific measures with generic measures applicable to a variety of conditions. Generic measures aimed at severely debilitating disease a re less appropriate than measures designed for use in the general popu lation. Asthma-specific measures should emphasize the incidence and im pact of such symptoms as coughing, wheezing, sputum production, and sh ortness of breath. Current procedures for computing utility scores and cost-benefit ratios based on them have serious measurement limitation s, and use of such scores should be postponed until those limitations are overcome. These assessment issues should be addressed separately f or adults and children.