There is limited evidence that contracts can potentially contribute to improving adherence, but there is insufficient evidence from large, good quality studies to routinely recommend contracts for improving adherence to treatment or preventive health regimens.
Enhancing commitment improves adherence to a medical regimen.
A commitment-based intervention was evaluated for improvement of adherence to a 10-day antibiotic regimen. Experimental Ss made verbal and written commitments for adherence and completed tasks designed to increase their investment in a medication regimen. Control Ss performed similarly structured tasks unrelated to the medical regimen. Adherence, measured by unannounced pill counts, was significantly higher for experimental subjects than for control Ss. Self-reported adherence was significantly correlated with posttest self-efficacy but not with pretest self-efficacy. Adherence to a medical regimen may be improved by strategies conceptually based on the investment model of commitment, which provides a useful framework for further study of adherence.