Reproducibility of data collected by patient interview

This study examined the reproducibility of data, not generally considered at risk for poor patient recall, obtained on two separate occasions. Our study used data collected for a register of heart attacks in the Lower Hunter Region of New South Wales, and included 1675 patients who were registered at least twice. Reporting inconsistencies between occasions were assessed for eight data items. We found that the sex of five patients had been recorded differently on the two occasions. Among patients interviewed on both occasions, between 0.5 per cent and 2.0 per cent of patients had inconsistent reports for marital status, country of birth, smoking status and height, 2.7 per cent for date of birth, 13 per cent for education level and between 1.6 per cent and 9.6 per cent for the history of various medical conditions. Patients not from an English‐speaking background, over 60 years of age or without tertiary education tended to have higher rates of inconsistent reporting. Time between occasions, marital status and sex were not associated with increased rates of inconsistent reporting. We concluded that apparently straightforward data items, such as date of birth and education level, were not perfectly reproducible when obtained by patient interview on separate occasions. Our results provide a starting point for sensitivity analysis in other studies if the potential inaccuracies in reporting of such data should be of concern.