Telephone Call Reminders Did Not Increase Screening Uptake More Than SMS Reminders: A Recruitment Study Within a Trial

Abstract

To compare the response rates and costs of phone call versus short message service (SMS) screening reminders to prospective randomised controlled trial (RCT) participants. A randomised evaluation within a large Australian diabetes prevention RCT. Participants were men aged 50-74 years, overweight or obese, without a previous Type 2 diabetes diagnosis. Those eligible on a pre-screening questionnaire who did not attend a further screening assessment within four weeks were randomised to receive an SMS or phone call reminder (N=709). The primary outcome was attendance for further screening assessment within eight weeks of pre-screening. Attendance was 18% (62/354) in the SMS reminder group and 23% (80/355) in the phone reminder group, with no statistically significant difference in response according to reminder type (RR=1.29, 95% CI 0.96-1.73, p=0.09). The lower confidence limits for response to SMS (95% CI 14% - 22%) and phone reminders (95% CI 18% - 27%) did not include the eight-week attendance rate prior to this evaluation, 12%. Phone reminders cost substantially more than SMS reminders (AU$6.21 versus AU$0.53 per reminder). SMS reminders were as adequate a method as phone reminders to boost RCT screening uptake, and were considerably more affordable.