Randomized controlled study of customized preventive medicine reminder letters in a community practice.

OBJECTIVE To test the effectiveness of customized, family-oriented reminder letters in activating patients to seek appropriate preventive services. DESIGN Randomized clinical trial. One group received computer-generated, customized letters explaining recommended preventive procedures for each family member. A second group received a form letter listing recommendations for all preventive procedures for all age and sex groups. A third group (control group) received no letters. SETTING A private medical centre, without university affiliation, in rural Quebec. PARTICIPANTS From 8770 patients who met study criteria, 719 families were randomly selected. Data were available for 1971 of 1998 patients in these families. MAIN OUTCOME MEASURES The Family Received Index is the proportion of all procedures for which a family was overdue that they received. The Family End-of-study Up-to-date Index is the proportion of procedures for which the family was eligible and for which they were up-to-date at the end of the study. RESULTS The Family Received Index for families mailed customized letters was more than double the index for patients not mailed letters (Kruskal-Wallis P = .0139). Comparison of the Family End-of-study Up-to-date indices also demonstrated that families of patients sent customized letters were more likely to be up-to-date than families not sent letters (Kruskal-Wallis P = .0054). No statistically significant difference appeared between the number of preventive measures received by the control group and the form-letter group. CONCLUSIONS This study demonstrates a clinically small but statistically significant value to customizing reminder letters.