Table 1 Stakeholder engagement in all phases of the study

Establish need and formulating research question

Marshallese stakeholders prioritized prevention of type 2 diabetes as the top health concern and risk in the community

Choosing comparator interventions

The two interventions/comparators (The WORD DPP and PILI ‘Ohana DPP) were chosen because they met the Marshallese stakeholders criteria: engaged family and friends, incorporated faith and FBO leaders, included cultural adaptations

Design

Marshallese stakeholders initially wanted participants and FBO to choose which intervention they receive. In-depth discussion was needed to explain the need for random assignment

Unit of randomization

Marshallese stakeholders input helped identify importance of randomizing at the FBO level rather than the participant level to reduce contamination

Outcomes of importance, instruments and measures

Marshallese stakeholders and the research team agreed that percent body weight change from baseline to 6 months was the primary outcome. Self-reported measures for behavioral changes and family support were chosen based upon Marshallese stakeholders’ input

Based upon Marshallese stakeholders input, scales for many instruments were adapted and refined to maximize construct validity among Marshallese participants. The total number of items was reduced by 36%

Recruitment

Based upon Marshallese stakeholders input, multiple recruitment methods were used to supplement FBO recruitment, including clinical referrals and social media

Data collection intervals, remuneration, and retention

Marshallese stakeholders believed that pre/post test data collection was sufficient; significant education was needed to gain agreement on 12 month post-intervention data collection. Marshallese stakeholders developed a draft retention plan that includes the utilization of a case management approach that incorporated both Marshallese research staff and Marshallese faith-based liaisons. Based upon stakeholder input, remuneration amounts increase as the study progresses to incentivize retention in the study, and closed Facebook groups were set up to allow participants to stay connected to study staff

Staffing and resource sharing

Marshallese stakeholders determined that Marshallese bilingual and bicultural research staff at the university should be responsible for recruitment, data collection, teaching interventions’ educational sessions, and study coordination. The university contracted with community based organizations to provide translation services, assist with recruitment, and facilitate dissemination. In addition, seven FBO liaisons were hired to assist with recruitment, retention, and intervention implementation. Marshallese stakeholders determined the appropriate compensation for community co-investigators, the two stakeholder advisory boards, and participants

Language

All written materials, including consent and educational materials are provided in both English and Marshallese. All stakeholder meetings and intervention sessions are facilitated in Marshallese

Dissemination

Marshallese stakeholders articulated that updates on the study’s progress (recruitment, enrollment, study progress, etc.) was as important as dissemination of the final results. Study updates are provided to the two advisory boards quarterly. In addition, broader community town hall meetings are to be held biannually to provide study updates