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 commented that the targeted methods for comparing more than two interventions in an observational study could be biased because the individuals counted in the study appeared to be only those who stayed on the comparison medication for a specific period of time. Thus, although an important outcome was major adverse events, those individuals who experienced those events early in treatment would not be included in the analyses. The researchers explained that they based their analyses on the sample of individuals who were on the targeted treatments 60 days after treatment onset, avoiding inclusion of patients who might have experienced adverse events unrelated to the treatments. In addition, the researchers noted that they applied an intention-to-treat analysis and each patient was followed for three years or until death based on their original group assignment. Any changes in treatment that occurred during that period did not change patients’ treatment group category, but the researchers did consider the amount of time patients were on the index treatments in their analyses.
  • The reviewers asked whether the period of time used to assess patient outcomes differed for different patients. The researchers replied that they followed all patients for three years unless the patients died during that period. They accounted for the different periods of follow-up time by using both major cardiovascular events and all-cause mortality as outcomes, rather than just major cardiovascular events.
  • The reviewers asked why the researchers used a fixed period of six months as a baseline period to assess the health condition of individuals before they received the experimental intervention. The researchers said they decided on this design after consultations with clinical experts and to be in line with other clinical trials they cited.

Conflict of Interest Disclosures

Project Information

Roee Gutman, PhD
Brown University
Estimation of Multi-Treatment Effects from Observational Data with Application to Diabetes Mellitus

Key Dates

September 2014
January 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
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: March 4, 2022