Effectiveness of Community-Based Lifestyle Interventions in the Prevention and Management of Type 2 Diabetes Mellitus: A Systematic Review Protocol.

Abstract

Type 2 diabetes mellitus (T2DM) affects hundreds of millions of adults worldwide and imposes an escalating clinical and economic burden, particularly in low- and middle-income countries. While landmark trials have shown that structured lifestyle interventions can substantially reduce T2DM incidence, translating these findings into scalable, community-embedded programmes remains challenging, and existing systematic reviews have inadequately addressed multicomponent designs, LMIC contexts, implementation outcomes, and cost-effectiveness. This protocol describes a systematic review and meta-analysis, conducted per PRISMA-P and PRISMA 2020 standards and guided by the Cochrane Handbook, that will evaluate the effectiveness of community-based lifestyle interventions (CBLIs) for both T2DM prevention in high-risk adults and management in adults with established disease. Eight major databases plus trial registries and grey literature will be searched from 2000 onward, with two reviewers independently screening records, extracting data, and assessing risk of bias using RoB 2 and ROBINS-I. Primary outcomes include HbA1c, fasting plasma glucose, and T2DM incidence; secondary outcomes span cardiometabolic markers, quality of life, behavioural change, cost-effectiveness, and implementation metrics (reach, fidelity, equity). Where data permit, random-effects meta-analysis will be performed, with heterogeneity explored through pre-specified subgroup and sensitivity analyses; otherwise, narrative synthesis following SWiM guidelines will be used. Certainty of evidence will be graded using GRADE. By synthesising effectiveness, implementation, and economic evidence across diverse community settings, this review is expected to clarify which CBLI models work best, for whom, and in what contexts—informing policy and practice decisions for scaling diabetes prevention and management programmes globally.