Results Summary

What was the research about?

Sometimes a study can get better results using data from different sites. In these cases, researchers may want to share patient data, including personal and private information such as dates of birth and addresses. However, researchers may not want to share data across sites because of worries about patient privacy. Some statistical methods can change patients’ sensitive individual data into summary data that hides individuals’ personal information. These privacy-protecting methods, or PPMs, make it safe to share data across sites. But researchers don’t know if PPMs produce accurate results.

In this study, the research team compared combinations of PPMs with methods that use patients’ individual data.

What were the results?

PPMs provided similar results to methods that used patients’ individual data. Some PPMs worked better than others.

What did the research team do?

The research team used a computer program to create data that mimicked real patient data. The team used three ways to change the individual data into summary data. Then they analyzed the summary data using a combination of PPMs. The team compared the results they got using summary data with results from individual data. Finally, the team tested the PPMs using real-world data.

Patients, researchers, and hospital staff provided input during this study.

What were the limits of the study?

The research team studied only some PPMs and types of data. Results may differ with other PPMs or data.

Future research could test PPMs in other research studies with data from different sources.

How can people use the results?

Researchers can use the results when considering how to share data across research sites.

Final Research Report

View this project's final research report.

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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. The comments and responses included the following:

  • Reviewers raised concerns about how representative the viewpoints of the stakeholders selected for interviews could be expected to be. In particular, reviewers noted that the policies and procedures of the institutional stakeholders’ organization, Kaiser Permanente, could influence the institutional stakeholders’ views. The researchers stated that they did not believe organizational policies or practices would impact more scientific discussions. However, they addressed the reviewers’ concerns by discussing the selective nature of their stakeholders and the potential impact on their Aim 1 findings in their limitations section.
  • Reviewers suggested adding a brief summary of the strengths and limitations of each methodological approach described to stakeholders. The researchers added a table to the discussion section summarizing the strengths and limitations of the analytic approaches considered in this study. The table also provides ranks of the various methods under different scenarios, so that it can guide stakeholders who might be choosing among these methods for their own analyses.
  • Reviewers asked the researchers to provide more of a summary of qualitative findings from their interviews with stakeholders and patients. The researchers explained that they would have liked to be able to summarize findings, but there was considerable variability between and within different stakeholder groups regarding priorities and preferences for data sharing. The researchers felt that this variability was an interesting finding in itself.
  • Reviewers suggested adding a glossary of key terms, primarily noting the interchangeable use of the terms, privacy and confidentiality. The researchers instead aimed to improve clarity by largely omitting the term, confidentiality, assuming other terms were less confusing.

Conflict of Interest Disclosures

Project Information

Darren Toh, ScD, BPHAR, MS
Harvard Pilgrim Health Care ,Inc.
Privacy-Preserving Analytic and Data-Sharing Methods for Clinical and Patient-Powered Data Networks

Key Dates

September 2014
April 2019

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
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Last updated: April 12, 2024