Results Summary

What was the research about?

Type 2 diabetes is a long-term health problem that causes blood sugar levels to rise. The rate of diabetes among the Marshallese, a Pacific Islander population living in the United States, is four times higher than that of the general population.

In this study, the research team worked with Marshallese people living in Arkansas and Oklahoma to adapt the Diabetes Prevention Program, or DPP, for Marshallese adults with obesity or overweight. DPP is a program shown to reduce risk factors for diabetes, such as having obesity. It promotes exercise and healthy eating. The team adapted and compared two six-month programs:

  • Wholeness, Oneness, Righteousness, Deliverance, or WORD DPP. This version focused on using faith to help people make healthy lifestyle changes. It had 16 group sessions. Community educators used pictures and analogies in sessions about faith and health.
  • Partnership for Improving Lifestyle Intervention, or PILI DPP. This version focused on Pacific Island culture, using social networks to help people make healthy lifestyle changes. It had 14 group sessions with topics such as how families can be active together or how to share health goals with family and friends. Community educators encouraged participants to keep a daily log of their weight, exercise, and diet.

The research team looked at weight loss and other health outcomes.

What were the results?

Six months after the programs ended, few people in each program lost weight. In both programs, only 7 percent of people lost at least 5 percent of their body weight. People in the two programs didn’t differ in:

  • Weight loss
  • Blood sugar levels or blood pressure
  • Exercise or healthy eating
  • Confidence in managing their health
  • Social support

Who was in the study?

The study included 380 Marshallese adults with overweight or obesity. Of these, 27 percent had pre-diabetes and 48 percent had type 2 diabetes. The average age was 42, and 57 percent were women. All lived in Arkansas and Oklahoma.

What did the research team do?

The research team assigned 31 churches by chance to offer WORD DPP or PILI DPP. People took part in the program assigned to their church. For both programs, a trained community educator led the 90-minute group sessions in Marshallese and English over 6 months.

At the start of the study, right after the programs ended, and six months later, the research team measured patients’ weight, blood sugar levels, and blood pressure. Patients also completed surveys.

People from the Marshallese community and healthcare providers were members of the research team.

What were the limits of the study?

COVID-19 made it hard for patients to attend in-person sessions and stay in the study, which may have affected study results. The study included Marshallese adults in two states. Results may differ in other places or for people from other backgrounds.

Future research could look at other ways to help Marshallese adults lose weight and prevent diabetes.

How can people use the results?

Health centers that serve Marshallese patients can use these results when considering ways to support weight management.

Final Research Report

View this project's final research report.

Peer-Review Summary

Peer review of PCORI-funded research helps make sure the report presents complete, balanced, and useful information about the research. It also assesses how the project addressed PCORI’s Methodology Standards. During peer review, experts read a draft report of the research and provide comments about the report. These experts may include a scientist focused on the research topic, a specialist in research methods, a patient or caregiver, and a healthcare professional. These reviewers cannot have conflicts of interest with the study.

The peer reviewers point out where the draft report may need revision. For example, they may suggest ways to improve descriptions of the conduct of the study or to clarify the connection between results and conclusions. Sometimes, awardees revise their draft reports twice or more to address all of the reviewers’ comments. 

Peer reviewers commented and the researchers made changes or provided responses. Those comments and responses included the following:

  • Some reviewers indicated that the lack of significant differences between the two weight-loss interventions and the high participant attrition rate were a result of inadequate engagement of community members in the study. The reviewers interpreted the report’s description of patient and stakeholder engagement to indicate that there was considerable disagreement and debate in the community regarding this study. The researchers disagreed with the reviewers, stating that healthy debate indicated strong community engagement and partnership and that changes made to the study protocol indicated a successful collaboration where both researchers and stakeholders listened to each other’s ideas and concerns.
  • The researchers requested more discussion about the implications of the study results, particularly the lack of effect for the two weight-loss interventions based on the Diabetes Prevention Program in this population. The reviewers hypothesized that this lack of effect indicated problems with intervention delivery, low participant and community engagement, and high rates of missing data.  The researchers expanded their discussion around potential reasons for the lack of significant findings in this study. They stated that the findings are most likely related to the well-known difficulties with losing weight, compounded by social, economic, and environmental barriers to weight loss in the Marshallese population.
  • The reviewers asked for clarification on how the researchers accounted for cluster in these analyses, since participants were clustered within churches and each church was randomized to one intervention or the other. The reviewers hypothesized that the sample size did not provide enough power to detect differences between groups because cluster was not taken into account in the power analyses. The researchers assured reviewers that they did consider clustering in all of their longitudinal analyses and in their power calculations and that the observed differences in outcomes between the two groups were too small to be considered significant.
  • The reviewers questioned the researchers’ approach to accounting for missing data because the reviewers did not believe missing data could be considered missing at random since they were connected to study attrition. In response the researchers ran additional analyses that demonstrated no differences in the results based on whether the data were thought to be missing at random.

Conflict of Interest Disclosures

Project Information

Pearl McElfish, PhD, MS, MBA
University of Arkansas for Medical Sciences
Comparative Effectiveness of Diabetes Prevention Programs

Key Dates

December 2016
December 2021

Study Registration Information


Has Results
Award Type
Health Conditions Health Conditions These are the broad terms we use to categorize our funded research studies; specific diseases or conditions are included within the appropriate larger category. Note: not all of our funded projects focus on a single disease or condition; some touch on multiple diseases or conditions, research methods, or broader health system interventions. Such projects won’t be listed by a primary disease/condition and so won’t appear if you use this filter tool to find them. View Glossary
Populations Populations PCORI is interested in research that seeks to better understand how different clinical and health system options work for different people. These populations are frequently studied in our portfolio or identified as being of interest by our stakeholders. View Glossary
Intervention Strategy Intervention Strategies PCORI funds comparative clinical effectiveness research (CER) studies that compare two or more options or approaches to health care, or that compare different ways of delivering or receiving care. View Glossary
State State The state where the project originates, or where the primary institution or organization is located. View Glossary
Last updated: April 23, 2024