Multiple reminders were more effective than single reminders for increasing the rate of diabetic retinopathy examinations
ACP J Club. 1999 Nov-Dec;131:80. doi:10.7326/ACPJC-1999-131-3-080
Halbert RJ, Leung K-M, Nichol JM, Legorreta AP. Effect of multiple patient reminders in improving diabetic retinopathy screening. A randomized trial. Diabetes Care. 1999 May;22:752-5. [PubMed ID: 99265080]
In adults with diabetes mellitus, are multiple mailed reminders more effective than single reminders for ensuring that annual diabetic retinal examinations are done?
Randomized, unblinded, controlled trial with 12-month follow-up.
A health maintenance organization (HMO) in California, United States.
All adults enrolled in the HMO (n = 23 740) were included. Follow-up was 83% (all patients who had not withdrawn from the HMO) (37% < 65 y of age) at 12 months.
At baseline, all physicians received educational materials on diabetic retinopathy, including the American Diabetes Association guidelines on diabetic retinopathy screening and a list of their patients with diabetes and the patients' diabetic retinopathy screening status. In addition, all diabetic patients without a record of retinopathy examination received educational materials and a reminder about diabetic retinopathy screening. 11 992 adults were allocated to the multiple-reminder group; those without a record of retinopathy screening at baseline received repeated reminders to have an examination at 3, 6, and 9 months. 11 748 patients were allocated to the single-reminder group and received no further information or reminders.
Main outcome measure
Completed retinopathy examinations as determined from data from HMO ophthalmologists and optometrists.
More adults in the multiple-reminder group had a diabetic retinopathy examination by 1 year (P = 0.023) (Table). The second reminder (at 3 mo) was the only effective additional reminder for increasing the rate of examination. Printing and postal costs were U.S. $80 per additional retinopathy examination.
Second reminders sent to adults with diabetes mellitus increased the rate of diabetic retinopathy examination.
Source of funding: No external funding.
For correspondence: Dr. A.P. Legorreta, Health Benchmarks, Inc., 21650 Oxnard Street, Suite 2150, Woodland Hills, CA 91367, USA. FAX 818-676-5344.
Table. Multiple vs single reminders to improve the rate of retinopathy examinations in adults with diabetes mellitus at 1 year*
|Multiple reminders||Single reminders||RBI (95% CI)||NNT (CI)|
|37.0%||35.4%||4.4% (0.6 to 8.4)||64 (34 to 452)|
*Abbreviations defined in Glossary; RBI, NNT, and CI calculated from data in article and supplied by author.
Screening and treatment of diabetic retinopathy prevent vision loss (1). Many organizations advocate annual retinal screening for all patients with diabetes (1), but screening is not always done, either because health care professionals do not recommend it or the patients do not comply with appointments (2). Halbert and colleagues' well-done trial studied > 23 000 patients with diabetes mellitus who were eligible for diabetic retinopathy screening.
Although not stressed by the authors, it has been shown (3) that the first reminder initially increased screening rates considerably (by approximately 30%). The effect of further reminders was statistically significant but much smaller (a 4.4% relative increase) and seemed to be correlated only to the second reminder. This ceiling effect has been noted by others (4). Reminders have a finite period of usefulness (in this case, 4 mo). However, the trial does suggest that single reminders for appropriate health-promotion and health-protection activities are not necessarily more cost-effective than multiple reminders. $80 per additional examination is probably a good investment for preventing future visual decline.
Further research is needed to refine the population most likely to act on reminders (would results have been improved if physicians had also received the additional reminders?), the message to be conveyed, and the method of conveying the message.
Pat Phillips, MBBS, MA
Queen Elizabeth HospitalWoodville, South Australia, Australia
3. Legorreta AP, Hasan MM, Peters AL, Pelletier KR, Leung KM. An intervention for enhancing compliance with screening recommendations for diabetic retinopathy. A bicoastal experience. Diabetes Care. 1997;20:520-3.
4. Richardson A, Williams S, Elwood M, Bahr M, Medlicott T. Participation in breast cancer screening: randomised controlled trials of doctors' letters and of telephone reminders. Aust J Public Health. 1994;18:290-2.