Development of a nurse-led, evidence-based, and theory-informed dietary intervention to modify multiple unhealthy dietary behaviors in gastric cancer survivors

Objective: This study aimed to report the development process of a nurse-led, evidence-based, and theory-informed dietary intervention designed to modify multiple unhealthy dietary behaviors in gastric cancer survivors and to describe its components. Methods: Following the 2008 Medical Research Council (MRC) framework, this study comprised two phases: “intervention development” and “feasibility assessment.” The development phase involved identifying the evidence base, selecting the theory, and modeling process and outcomes, resulting in an initial intervention. The feasibility assessment phase included a pilot randomized controlled trial to test the feasibility (eligibility, recruitment, retention, and attendance rates), acceptability (satisfaction with the intervention), and preliminary effectiveness of the initial intervention on six unhealthy dietary behaviors (insufficient intake of fruits, vegetables, and soybeans, as well as overconsumption of salt, processed meat, and alcohol). Results: The initial 4-week intervention, based on social cognitive theory, was led by a trained nurse and was individually delivered through one hospital-based face-to-face session plus three home-based telephone follow-ups. The pilot trial demonstrated that the initial intervention was largely feasible, well-accepted and showed preliminary effectiveness in improving fruit intake only. Conclusions: This study illustrated a systematic and rigorous process for developing a dietary intervention for gastric cancer survivors using the MRC framework. The initial intervention requires refinements to enhance its feasibility and effectiveness in modifying the other unhealthy dietary behaviors beyond insufficient fruit intake. It can also be adapted for survivors of other cancer types with similar unhealthy dietary behaviors. Trial registration: The trial was registered on the ClinicalTrials.gov website (Registration No. NCT04985084).