This paper reports an examination of cognitive processes used by 178 women aged 50 years and older in retrieving information about the frequency with which they received Papanicolaou smears, mammograms, and clinical breast examinations. Women were selected from a health maintenance organization in which they had been enrolled for at least 5 1/2 years. The literature suggested that reporting of regular events such as these kinds of tests is likely to be based on schemas, which is an estimation technique in which events are reported in a format with generic content. Thus, if the procedure is believed to occur annually, the respondent will report receiving five tests in 5 years. The study attempted to evaluate whether use of episodic recall, in which respondents are forced to report individual events, would be more accurate than reports based on estimation using a schema format. The results indicated that most of the errors occurred in Papanicolaou smear reporting, which is consistent with the literature, and that the fewest errors occurred with mammograms. Regardless of the questionnaire format, respondents persisted in using schemas based on the date of annual physical examination. Most reporting errors occurred because the interval between examinations was estimated incorrectly.