Rationale and design for a pragmatic effectiveness-implementation trial of online behavioral obesity treatment in...

Current guidelines recommend behavioral intervention to achieve a modest weight loss (e.g., 3-5%) as a first-line obesity treatment. Online behavioral obesity treatment, delivered via the Rx Weight Loss (RxWL) program, produces clinically significant initial weight losses. However, the program's pragmatic utility in routine medical care has yet to be tested. Further, additional research is needed to determine how best to extend the RxWL program to facilitate weight loss maintenance. This paper summarizes methods for a pragmatic trial aimed at identifying optimal methods for implementation of RxWL in primary care and evaluating relative effectiveness of two approaches to weight loss maintenance.

RxWL will be implemented in a network of approximately 60 primary care clinics. Implementation outcomes (program uptake and completion metrics) will be compared between a Basic Implementation Intervention consisting primarily of access to RxWL, and an Enhanced Implementation Intervention with additional training in strategies for motivating and supporting patients in their use of RxWL and online clinician support tools for tracking patient progress. Second, two intervention approaches (Monthly Lessons versus Refresher Courses) within the RxWL patient platform will be tested against an educational control condition, and effects on 1-year weight loss maintenance will be compared.

This study will provide essential information about the feasibility and utility of online obesity treatment in primary care. It will provide novel information on two approaches to weight loss maintenance for patients in this setting. This project fills key gaps in evidence regarding best practices for obesity treatment in primary care.