Signed family physician reminder letters to women overdue for screening mammography: A randomized clinical trial

Objective: To determine whether signed family physician reminder letters to women overdue for screening mammography prompts rescreening. Methods: A randomized double-blind trial conducted in 2013 among women aged 51-73 and overdue for screening by 6-24 months. The study was carried out by the publicly funded British Columbia Cancer Agency Screening Mammography Program, which routinely sends standard reminder postcards to women who are due for mammography. Participating family physicians signed letters for the overdue women in their practices. The overdue women were mailed either the signed reminder letter and the standard reminder postcard, or the standard reminder postcard alone. The primary endpoint was the proportion of overdue women that attended a screening mammogram appointment within six months of mailing the study letters. The analysis was by intention to treat. Results: In total, 822 family physicians participated and 5638 women were randomized. Mammography attendance by six months after mailing the reminders was 34.4% (947/2749) for women in the signed family physician letter arm, compared with 24.0% (660/2749) for women in the control arm (p < 0.0001). Adjusting for age, number of previous screening mammograms, and months overdue, women in the signed letter arm were significantly more likely to return for screening than women in the control arm (RR 1.41; 95% confidence interval: 1.30-1.54). Conclusion: A signed family physician reminder letter improved mammography attendance for women who were overdue for screening mammography.