Results Summary

What was the research about?

Obesity can lead to serious health problems such as high blood pressure, diabetes, and heart disease. Doctors offering different treatment choices may help patients with obesity lose weight.

In this study, the research team wanted to see if giving patients a choice of one or more weight-loss treatments helped them lose weight. The team offered five options:

  • Meal replacements
  • Weight-loss medicines
  • Weight Watchers® vouchers
  • Recreation center passes
  • Group lifestyle classes

Patients could choose one option at the start of the study and change or add options after six months. The research team compared the results for patients who used a weight-loss treatment to those who did not.

What were the results?

Over the course of the study, more patients who used a weight-loss treatment lost weight than patients who didn’t use a treatment. A total of 35 percent of patients who used a weight-loss treatment lost at least 5 percent of their weight. Only 16 percent of the patients getting usual care lost that much.

Patients who used a weight-loss treatment were more likely to lose at least 5 percent of their weight if they

  • Went to more of their monthly doctor visits
  • Added a second weight-loss treatment
  • Chose to take a weight-loss medicine

Of the patients selecting a treatment

  • 35 percent chose meal replacements
  • 28 percent chose weight-loss medicines
  • 22 percent chose recreation center passes
  • 7 percent chose Weight Watchers® vouchers
  • 5 percent chose group lifestyle classes
  • 2 percent wanted only monthly clinic visits

During the study, 55 percent of patients who selected a treatment changed that treatment at least once. As the study went on, more patients changed to medicines. More patients switched from meal replacements or recreation center passes than the other choices.

Who was in the study?

The study included 3,049 patients with obesity and at least one related health problem. Patients attended any of eight clinics serving patients with low incomes in the Denver, Colorado, area. Of the patients offered the choice of a treatment, 82 percent were white, 17 percent were black, and 1 percent were Native Indian or Alaskan. A total of 55 percent of patients identified as Hispanic or Latino. The average age was 50 and 70 percent were women.

What did the research team do?

Using health records, the research team created a list of patients with obesity from the eight healthcare clinics. The team assigned patients to one of two groups by chance. Patients in one group chose from a set of weight-loss treatments that the team had already found to work well. Of these 309 patients, 119 chose at least one treatment. During the one-year study, these patients visited a clinic and got weighed once a month. Patients choosing a treatment had to pay a $5 or $10 copay each month.

Patients in the second group received usual care and visited their doctors at least once during the study. The doctors gave patients information about a weight-loss treatment only if they asked for it. Of these patients, 12 percent asked their doctor for information about a weight-loss treatment, and the doctors provided it. 

The research team collected weight information from patients’ health records. In addition, the team looked at health records to see what weight-loss program choices patients in the treatment group made.

What were the limits of the study?

The study included patients from only one healthcare system. The results may be different for patients in other places.

Future studies could look at whether patients’ health conditions improve because of their weight-loss choices.

How can people use the results?

Doctors can use the results when considering similar ways to help patients lose weight. Health insurance companies could include these weight-loss-treatment choices in their plans.

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:

  • The reviewers asked for more information about the weight-management interventions that were already being used in the comparison group and how those were assessed. The researchers explained in their revision that they used chart review to identify what interventions were used in the comparison group.
  • Given the pragmatic, not-randomized nature of this trial, the reviewers asked for more detail on how the researchers accounted for potentially confounding variables. The researchers added information to describe how they used generalized linear mixed models to address confounders.
  • In a related comment, the reviewers expressed concern that the researchers did not adequately address differences among the study sites and differences in the number of observations and number of clinic visits per patient. The researchers described how they addressed these concerns. They also stated that they had looked for any differences in non-study-related visits between groups and found none.
  • The reviewers asked for more information on how the researchers measured patient adherence to the treatment modality. The researchers explained that they measured adherence based on visits to the weight clinic, group weight-loss classes, and the recreational center. They were unable to use other types of adherence measures because clients were inconsistent in their use of reporting tools.
  • The reviewers stressed the importance of addressing the PCORI Methodology Standards related to data registries in the final report. The researchers provided this information, noting in their response that they had added information about how they dealt with patients who dropped out, were excluded, or were lost to follow-up.

Conflict of Interest Disclosures

Project Information

Daniel Bessesen, MD
Denver Health and Hospital Authority
A Toolbox Approach to Obesity Treatment in Primary Care

Key Dates

May 2013
May 2018

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: January 25, 2023