Results Summary

What was the research about?

Comparative effectiveness research compares two or more treatments to see which one works better for which patients. Sometimes, groups of people respond differently to the same treatment. For example, women might, on average, receive more benefit from a treatment than men do. If researchers group women and men together when they analyze study data, they may miss this difference and overlook some of the benefits of a treatment.

Researchers can analyze data on the effects of a treatment in many ways. Each way has strengths and weaknesses. Bayesian regression is one method that allows researchers to consider various factors in their analysis, such as patients’ ages, sex, or health problems. This method can help researchers understand how different groups of people respond to a treatment. But it requires advanced computer programs that are not readily available to all researchers.

In this study, the research team wanted to make it easier for researchers to use Bayesian regression.

What were the results?

The research team created a new type of software. The software helps researchers use Bayesian regression to understand how different groups of people respond to a treatment. The team also provided

  • Instructions on how to use the software
  • A detailed example using data from a past study on heart disease
  • Tips to help researchers know how best to analyze data and report the results

What did the research team do?

First, the research team identified the best ways to use Bayesian regression to understand how different groups of people respond to a treatment. The research team then designed the new software. During the study, the team worked with a panel of experts in statistics. The panel gave input on the best ways to use Bayesian regression. The panel also gave feedback on the software.

To find out how best to analyze data and report results, the team talked with the panel. The team also reviewed studies on methods to understand how different groups of people respond to a treatment.

What were the limits of the study?

The software only works for randomized controlled trials, a type of study where researchers assign the treatment a patient receives by chance. Future research can look at how to develop software for other types of studies.

How can people use the results?

Researchers can download the software from this study for free. The software may help researchers to see when treatments work well for some groups of people but not for others.

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.

The reviewers found this Methods-focused report to generally be very strong, but said they would like illustrations of the methods developed as part of the study. These recommendations were also intended to make the report more understandable to general scientist audiences. The investigators added examples of the methods in the report, and also acknowledged that their new software package, beanz, applies to only some forms of patient-centered outcomes research. There were no scientific concerns.

Conflict of Interest Disclosures

Project Information

Ravi Varadhan, PhD
Johns Hopkins University
Filling Two Major Gaps in the Analysis of Heterogeneity of Treatment Effects for Patient-Centered Outcomes Research

Key Dates

September 2013
July 2017

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
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 11, 2024