Compliance with inhaled medications: The relationship between diary and electronic monitor

Abstract

Self-report is a frequently-used method of assessing compliance with prescribed medications in patients with chronic illnesses. Most researchers agree, however, that self-report misrepresents patient adherence to regimen prescription. In this randomized, controlled study evaluating inhaler medication compliance, diary data was compared to electronic monitoring in 55 adults with asthma. Subjects randomized to the treatment group received a six-week self-management program. An electronic monitor, the MDI Chronolog, was used in this study to assess inhaler use. The MDI Chronolog records the date and time of each inhaled activation. The self-report measure used was a daily asthma diary. Subjects were asked to use their inhaled medications as usual and record the date and time they administered their medication over a one-week period. Moderate correlations (r_s=.55, Mdn_d=95.8, Mdn_c=91.6) were found when comparing the number of administrations calculated using the MDI Chronolog to the number of administrations reported in the subject's diary. When the dosing interval was examined, however, the correlation was weaker (r_s=.44, Mdn_diary=92.8, Mdn_chronolog=37.5). In each case, self-reported compliance was higher than monitored adherence.