The Bangladesh Diabetes: Community-Led Awareness, Response and Evaluation (DClare) cluster randomised controlled trial data.

The full methods for the cRCT have been described in the published study protocol, trial registration and main trial results publications:

· Original trial protocol for a stepped-wedge trial: https://doi.org/10.1186/s13063-021-05167-y

· Updated trial protocol for a cRCT, due to the COVID-19 pandemic: https://doi.org/10.1186/s13063-023-07243-x

· Trial registration: https://doi.org/10.1186/ISRCTN42219712

Briefly, Alfadanga upazila was divided into 12 clusters of approximately equal population size using government census data. Within these 12 clusters, between 2-5 villages were purposefully selected to achieve between 800-1000 households per cluster, according the following eligibility criteria: a) they do not sit on a border with a neighbouring study cluster; b) they are not a major trading centre or administrative centre; c) they have a minimum of 50 households. A population census was conducted between November 2019 – January 2020 to form a sampling frame, with each household within purposefully selected villages visited, and all household members aged 25 and older registered. A unique study ID was assigned to each individual using the following formulation.

Clusters were randomised to either control or community mobilisation through Participatory Learning and Action (PLA), which works through facilitated community groups actively engaging communities in identifying the causes of health problems and working together to design and implement ways to address these health problems, and reflect on their progress.

Three cross-sectional surveys were conducted: a) pre-COVID-19 baseline; b) post-COVID-19 baseline; c) endline. For each survey, a random sample of individuals were selected using two-stage simple random sampling, with the household randomly selected then one eligible individual selected from these households. For the endline survey, individuals who were identified as living with intermediate hyperglycaemia in the post-COVID-19 baseline survey were purposefully selected.