Agreement between women's histories of oral contraceptive use and physician records

The histories of oral contraceptive (OC) use provided by women participating in a study of hepatocellular adenoma (HCA) were compared with records obtained from their physicians. In the HCA study two memory aids were used to assist women in their recall: a calendar of significant events during a woman's lifetime to which she might relate her use of OCs and a book of colour photographs of the 90 OC preparations available up to the time of the study. Using the number of months of a woman's history which could be checked against physician records (mean for all women of 33 months) as the denominator, the highest proportion of concordance was for month-specific duration of OC use (90%) with lower agreement for duration and brand (62%) and duration, brand, and dose (54%). Agreement was better for cases than for controls.