Objective: Prompting may promote engagement with behavior change interventions. Prompts can be delivered inexpensively via automated voice response (AVR) reminders or short message service (SMS) text messages. We examined the association between participants' characteristics and preferred reminder modality.
Methods: Healthy Directions 2 is a cluster randomized controlled trial implemented in Boston, Massachusetts to promote change in multiple behavioral cancer risk factors. At baseline (2009), participants completed a survey assessing socio-demographics, health status, height/weight, and factors associated with technology. One-third of participants randomized to receive the intervention (n=598) were randomized to receive automated reminders, with participants selecting modality.
Results: 28% (167/598) of participants selected SMS reminders. Controlling for clustering by primary care provider, younger participants (OR=0.97, 95% CI=(0.95, 0.99), p<0.01), those most comfortable with computers (very uncomfortable OR=0.54, 95% CI=(0.29, 1.01), p≤0.05: referent group = very comfortable), and those who frequently sent/received text messages (never OR=0.09 CI=(0.04, 0.16) p<0.01; 1-3 times/month OR=0.38, 95% CI=(0.15, 0.93) p=0.04: referent group=1-5 times/week) were more likely to choose SMS.
Conclusions: Interventions should make both modalities available to ensure that more participants can benefit from prompting. Studies examining the effect of automated reminders may have reduced effectiveness or generalizability if they employ only one modality.
Trial registration: ClinicalTrials.gov NCT01415492.
Copyright © 2012 Elsevier Inc. All rights reserved.