Which combinations of behaviour change techniques work best? Evidence from meta-review of interventions addressing healthy diet and exercise after breast cancer

Background The primary aim was to identify combinations including ≥ 3 behavior change techniques (BCTs) that are jointly used in behavioral interventions for women with/survivors of breast cancer, and result in a simultaneous improvement of physical activity, healthy nutrition behaviour, and healthy body weight maintenance. Methods A meta-review integrated evidence from systematic, scoping, and pragmatic reviews. Ten databases were searched using ASReviews software and through manual searches, resulting in the inclusion of 32 reviews. The ROBIS tool was applied to assess bias risk. All combinations of ≥ 3 BCTs were identified in the original studies, and ratios of studies indicating a significant improvement to those with no improvement were calculated for three outcome domains. BCT combinations used in ≥ 10 original intervention studies (with ≥ 3 studies per each outcome domain) and supported in ≥ 85% of intervention studies were identified as the most promising. Results A total of k = 17,715 combinations were identified, including 3–12 BCTs. Only 46 combinations met the criteria for the most promising ones (supported by ≥ 85% of studies), with 7 combinations supported in ≥ 90% of studies. The promising combinations contained 3–6 BCTs included the following: goal setting (behaviour), problem solving, demonstration of the behaviour, self-monitoring of behaviour, instruction on how to perform the behaviour, feedback on behaviour, credible source. Interestingly, goal setting (related to behaviour or outcome) was present in 22 of the supported combinations, whereas demonstration of behaviour, problem solving, and self-monitoring were included more frequently (33, 32, and 26 of supported combinations, respectively). Conclusions This meta-review offers a novel approach to identifying BCT combinations that are jointly used in interventions resulting in an improvement in physical activity, healthy nutrition behaviour, and healthy body weight maintenance. These evidence-based combinations may serve as examples of good practices for promoting a healthy lifestyle in the context of breast cancer. Trial registration PROSPERO database registration: #CRD420251130311.