Key points are not available for this paper at this time.
Patients were followed for 2 yr after an attack of peptic ulcer. Intake of an antacid regimen was monitored objectively. Quantitative data were obtained on error in statements about intake (i.e., “compliance”) made by 116 patients and errors in estimates of “compliance” made by 3 physicians. Although patients said their intake of antacid averaged 89% of the amount prescribed, their actual intake averaged only 47%. For patients who claimed they took 100%, intake variedfrom 2% to 130% with a mean of 59%. Patients who admitted missing only an occasional dose actually missed substantially more doses than those who claimed 100% compliance. Estimates of intake made by the 3 physicians were more accurate than patients' statements but averaged 50% higher than actual intakes. In patients with low intakes (median 13%), the median estimate by physicians was 55%—an overestimate of 400%. The correlation between actual intakes and physicians' estimates was +0.48, indicating that physicians' judgements were significantly better than chance but nevertheless low in accuracy. Physicians' accuracy did not improve as they gained familiarity with the patient. Demographic data were of limited value in estimating intake. These observations, along with others cited in the literature, indicate the importance of series of objective and quantitative measures of medicine intake. A single measurement, even though accurate, may be grossly misleading because monthly antacid intake for a given patient could vary from 80% above his mean (2 SD) to 80% below, and daily fluctuation could be even larger.
Roth et al. (Wed,) studied this question.