Adherence to single daily dose of aspirin in a chemoprevention trial. An evaluation of self-report and microelectronic monitoring
K. D. Burney, K. Krishnan, M. T. Ruffin, D. Zhang and D. E. Brenner
Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, USA.
A consecutive sample of 64 healthy adults (33 female and 31 male) were
recruited at the University of Michigan Medical Center, Ann Arbor. Data
were available for analysis on 57 subjects. The participants were asked to
take a single daily dose of aspirin ranging from 0 to 640 mg. Adherence to
the daily aspirin ingestion was measured by self-report and the Medication
Event Monitoring System (MEMS, Aprex Corp, Fremont, Calif); adherence rate
for the study population was 35%. The adherence rates for all dosing errors
between self-report and Medication Event Monitoring System were
significantly different (P = .002). There was no significant gender
difference in adherence rates. Adherence to regular aspirin ingestion was
poor in healthy, paid subjects despite explicit, written and verbal
instructions. Patient self-report alone is not a reliable measure of
adherence.
