The Measurement of Compliance: Medication Taking
Peter Rudd Stanford University Medical Center
This chapter reviews the special issue of medication taking with special emphasis on prescribed drugs and optimizing its measurement despite constraints of patient cooperation, evolving technology, and user effectiveness. The discussion addresses definitions and assumptions, historical developments, epidemiology, methods of measurement, linkage to therapeutics, and guidelines for clinicians and investigators.
Haynes ( 1979a) has defined compliance as the extent to which a person's behavior, in terms of taking medications, following diets, or making other lifestyle changes, coincides with medical advice. This broad definition further assumes a number of conditions ( Feinstein, 1975; Sackett, 1977). It first assumes that the medical condition under consideration has been properly diagnosed. Second, the definition presupposes that effective treatment exists in a form shown to produce more good than harm. Third, it presumes that the clinician provides the recommendations in understandable and achievable form. For example, suboptimal compliance might result if the prescription were offered in ambiguous language or at a cost prohibitive for a particular patient.
These assumptions are hardly trivial. They underscore that compliance for medication taking is usually situation specific and subject to multiple positive