Text-Message Reminders to Improve Sunscreen Use A Randomized, Controlled Trial Using Electronic Monitoring

Objective: To evaluate the effectiveness of cellular telephone text messaging as a reminder tool for improving adherence to sunscreen application. Design: We conducted a randomized, controlled trial of the effect of an electronic text- message reminder system on adherence to sunscreen application. Adherence to daily sunscreen use was evaluated using a novel electronic monitoring device. Setting: Participants were recruited from the general community. Participants: Seventy participants constituted a volunteer sample from the general community. The inclusion criteria required participants to be 18 years or older, to own a cellular telephone with text-message features, and to know how to retrieve text messages. Intervention: Half of the participants received daily text-message reminders via cellular telephone for 6 weeks, and the other half did not receive reminders. The text-message reminders consisted of 2 components: a "hook" text detailing daily local weather information and a "prompt" text reminding users to apply sunscreen. Main Outcome Measure: The primary end point of the study was adherence to sunscreen application measured by the number of days participants applied sunscreen during the 6-week study period. Results: All 70 participants completed the 6-week study. There were no statistically significant differences in baseline characteristics between the 2 study groups. At the end of the study period, the 35 participants who did not receive reminders had a mean daily adherence rate of 30.0% (95% confidence interval, 23.1%-36.9%). In comparison, the 35 participants who received daily text-message reminders had a mean daily adherence rate of 56.1% (95% confidence interval, 48.1%-64.1%) (P<.001). Among the participants in the reminder group, 24 (69%) reported that they would keep using the text-message reminders after the study, and 31 (89%) reported that they would recommend the text-message reminder system to others. Subgroup analysis did not reveal any significant demographic factors that predicted adherence. Conclusions: Despite awareness of the benefits of sunscreen, adherence is low, even in this population, for whom adherence was knowingly monitored. Shortterm data demonstrate that using existing cellular telephone text-message technology offers an innovative, low-cost, and effective method of improving adherence to sunscreen application. The use of ubiquitous communications technology, such as text messaging, may have implications for large-scale public health initiatives.