Effect of Serial Anthropometric Measurements and Motivational Text Messages on Weight Reduction Among Workers: Pilot Randomized Controlled Trial

BACKGROUND: Obesity is an endemic problem with significant health and financial consequences. Text messaging has been shown to be a simple and effective method of facilitating weight reduction. In addition, waist-to-hip ratio (WHR) has emerged as a significant anthropometric measure. However, few studies have examined the effect of serial anthropometric self-measurement combined with text messaging. OBJECTIVE: The primary aim of this study was to assess whether an 8-week program, consisting of weekly serial self-measurements of waist and hip circumference, combined with motivational text messages, could reduce WHR among Australian workers. METHODS: This was a community-based, participant-blinded, staggered-entry, parallel group study. Adult workers with access to mobile phones were eligible and recruited through an open access Web-based survey. Participants were randomly allocated to receive intervention or control messages for 8 weeks. Outcome data were self-assessed through a Web-based survey. RESULTS: A total of 60 participants were randomized with 30 participants each allocated to a control and an intervention group. There was no significant change in WHR (P=.43), and all secondary outcome measures did not differ between the intervention group and the control group at the end of the 8-week intervention. Both groups, however, showed a significant decrease in burnout over time (mean [SE]: pre 4.80 [0.39] vs post 3.36 [0.46]; P=.004). The intervention uptake followed a downward trend. Peak participant replies to weekly self-measurements were received in week 3 (14/23, 61%) and the least in week 8 (8/23, 35%). No harm was found to result from this study. CONCLUSIONS: This study is an innovative pilot trial using text messaging and serial anthropometric measurements in weight management. No change was detected in WHRs in Australian workers over 8 weeks; therefore, it could not be concluded whether the intervention affected the primary outcome. However, these results should be interpreted in the context of limited sample size and decreasing intervention uptake over the course of the study. This pilot trial is useful for informing and contributing to the design of future studies and the growing body of literature on serial self-measurements combined with text messaging. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12616001496404; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=371696&isReview=true (Archived by WebCite at http://www.webcitation.org/73UkKFjSw)