Recruitment challenges and recommendations for adolescent obesity trials

To report our experiences with recruiting overweight and obese 13- to 16-year-olds for the Loozit® weight management randomised control trial (RCT) and to identify effective strategies for recruiting adolescents from the community to a treatment trial.

The Loozit RCT is a two-arm, community-based, lifestyle intervention that aims to evaluate the effect of additional therapeutic contact provided via telephone coaching and electronic communications as an adjunct to the Loozit group programme. Strategic areas that were targeted to recruit adolescents included media, schools, health professionals and community organisations. The programme aimed to recruit a cohort of 12-16 adolescents (body mass index z-score range 1.0-2.5) aged 13-16 years every 3 months over 3 years. Information regarding recruitment and eligibility to participate was initially assessed during a telephone screen. The relative cost effectiveness of recruitment strategies was determined based on recruitment rates and costs including administrative costs and research assistant time.

Out of 474 enquiries, 32% resulted in an enrollment to the RCT. Newspaper articles and school newsletters accounted for nearly 60% of enquiries and enrollments and were the most cost-effective recruitment strategies. Common reasons for ineligibility for inclusion in the RCT were adolescents being too young (21%) and parents consenting but adolescents refusing to participate (17%).

The most successful recruitment strategies for the Loozit RCT were local newspapers and school newsletters. Future studies should consider involving a Public Relations department and other potentially cost-effective strategies such as peer recruitment.