Measuring adherence to medical treatments in childhood chronic illness: Considering multiple methods and sources of information

Adherence to medical treatment is a significant problem for children and ad olescents with chronic conditions, such as asthma, diabetes, and cystic fib rosis. The consequences of nonadherence can be serious, contributing to inc reased symptoms, unnecessary hospitalizations, and declines in physical fun ctioning. The quality of data obtained from clinical trials can also be aff ected by poor adherence, leading to erroneous conclusions concerning the ef ficacy of drug treatments and the dosages that are needed to achieve those effects. Adherence problems in both clinical research and practice also lea d to substantially higher health care costs. In order to further our unders tanding of the barriers that lead to poor adherence and identify strategies that are effective in addressing them, we need to develop reliable and val id measures of adherence behaviors. Using cystic fibrosis as a model of a s erious, chronic disease that requires a difficult and time-consuming medica l regimen, three different types of adherence measures are considered: self -report questionnaires, daily diary reports, and electronic monitors. The s pecific advantages and disadvantages of each type of measurement are review ed, and specific recommendations are made for future research.