Randomised controlled trial of alternative messages to increase enrolment in a healthy food programme among individuals with diabetes

BMJ Open. 2016 Nov 30;6(11):e012009. doi: 10.1136/bmjopen-2016-012009.

Abstract

Objectives: We compared the effectiveness of diabetes-focused messaging strategies at increasing enrolment in a healthy food programme among adults with diabetes.

Methods: Vitality is a multifaceted wellness benefit available to members of Discovery Health, a South Africa-based health insurer. One of the largest Vitality programmes is HealthyFood (HF), an incentive-based programme designed to encourage healthier diets by providing up to 25% cashback on healthy food purchases. We randomised adults with type 2 diabetes to 1 of 5 arms: (1) control, (2) a diabetes-specific message, (3) a message with a recommendation of HF written from the perspective of a HF member with diabetes, (4) a message containing a physician's recommendation of HF, or (5) the diabetes-specific message from arm 2 paired with an 'enhanced active choice'(EAC). In an EAC, readers are asked to make an immediate choice (in this case, to enrol or not enrol); the pros and cons associated with the preferred and non-preferred options are highlighted. HF enrolment was assessed 1 month following the first emailed message.

Results: We randomised 3906 members. After excluding those who enrolled in HF or departed from the Vitality programme before the first intervention email, 3665 (94%) were included in a modified intent-to-treat analysis. All 4 experimental arms had significantly higher HF enrolment rates compared with control (p<0.0001 for all comparisons). When comparing experimental arms, the diabetes-specific message with the EAC had a significantly higher enrolment rate (12.6%) than the diabetes-specific message alone (7.6%, p=0.0016).

Conclusions: Messages focused on diabetes were effective at increasing enrolment in a healthy food programme. The addition of a framed active choice to a message significantly raised enrolment rates in this population. These findings suggest that simple, low-cost interventions can enhance enrolment in health promoting programmes and also be pragmatically tested within those programmes.

Trial registration number: NCT02462057.

Keywords: DIABETES & ENDOCRINOLOGY; NUTRITION & DIETETICS; active choice; health promotion; messaging.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Diabetes Mellitus, Type 2* / diet therapy
  • Diet, Healthy*
  • Female
  • Health Promotion*
  • Humans
  • Male
  • Motivation
  • Patient Acceptance of Health Care / statistics & numerical data*
  • Patient Selection
  • Program Evaluation
  • South Africa / epidemiology
  • Text Messaging
  • Weight Reduction Programs*

Associated data

  • ClinicalTrials.gov/NCT02462057