Results Summary

PCORI funded the development of PCORnet®, the National Patient-Centered Clinical Research Network, to make it easier and more efficient to conduct research. PCORnet is made up of Partner Networks that harness the power of large amounts of health data and patient partnerships.

Clinical Data Research Networks (CDRNs) are one type of network supported by PCORI. CDRNs consist of two or more healthcare systems, including hospitals, integrated delivery systems, and federally qualified health centers. Each CDRN transforms data gathered from routine patient care across its participating health systems to a consistent format, the Common Data Model (CDM), to enable rapid response to research-related questions.

PCORI funded the Chicago Area Patient-Centered Outcomes Research Network’s (CAPriCORN) participation in PCORnet from 2015 to 2019. This report outlines CAPriCORN’s achievements in building its research infrastructure capacity to

  1. Create ways to involve patients, healthcare providers, health plans, and health systems in the research process and decision making about the network
  2. Continue building the PCORnet CDM to add new types of data, ensure data quality, answer questions and requests, link to data outside the network, and keep data secure and private
  3. Create an efficient infrastructure to carry out clinical trials
  4. Create rules and guidance to protect people who take part in research studies, keep participants’ information confidential, and examine the risks of proposed studies
  5. Work with PCORnet partners and partners outside the network to do research studies, build information systems, and share knowledge and practices
  6. Create a plan to fund the network after PCORI funding ends

Network at a glance

CAPriCORN collected data for nearly 10 million patients from private and public health systems in and around Chicago, Illinois. Led by Northwestern University, nine additional partners supported the network: AllianceChicago, Cook County Health and Hospitals System, Edward Hines Jr. VA Hospital and Jesse Brown VA Medical Center, Loyola University Health System, Lurie Children’s Hospital of Chicago, NorthShore University HealthSystem, Rush University Medical Center, University of Chicago, and University of Illinois Hospital and Health Sciences System. CAPriCORN’s goal was to improve the health of Chicago-area residents.

Title Chicago Area Patient-Centered Outcomes Research Network (CAPriCORN)
Network design Clinical Data Research Network (CDRN)
Lead partner Northwestern University
Other Partners AllianceChicago
Cook County Health and Hospitals System
Edward Hines Jr. VA Hospital and Jesse Brown VA Medical Center
Loyola University Health System
Lurie Children’s Hospital of Chicago
NorthShore University HealthSystem
Rush University Medical Center
University of Chicago
​University of Illinois Hospital and Health Sciences System
Participants 377 hospitals, healthcare centers, and primary care practices staffed by 74,000+ healthcare providers
Population 9,581,310 Chicago-area residents

How does the network operate?

CAPriCORN created a Steering Committee made up of one member from the lead organization and each partnering organization; two members from a committee representing patients and communities; and members from research, ethics, and administrative teams. The Steering Committee supervised how the partner sites collected and maintained data and oversaw other committees and work groups.

The Steering Committee approved research requests. The management team, located at Northwestern University, handled contracts. The network’s Institutional Review Board, or IRB, made sure studies were ethical and protected participants. The network’s data sets follow the Common Data Model (CDM), which helped CAPriCORN respond to requests from researchers. One of the network’s work groups made sure that the sites maintained high-quality data.

How did the network involve patients and other partners?

The network had a Patient Community Advisory Committee. Patients led this committee of 8–10 core members who provided feedback and guidance throughout all stages of the research process. These core members included veterans, community members, public health professionals, caregivers, patients, health systems leadership, and frontline clinicians. The group made sure that all studies included patients’ perspectives, contributed new information about the topic, and featured racially and ethnically diverse study populations. When possible, patients helped the lead researchers design or improve studies. Two members of the patient committee served as voting members on the Steering Committee. Patient committee members also served on the IRB as well as the ethics, communications, business, and coordinating committees. Additionally, each partner had its own community advisory participants.

Who is in the network?

As of March 2019, CAPriCORN’s database contains information on nearly 10 million individuals who have received care at healthcare centers across the greater Chicago region. Most data come from electronic health and billing records, although some sites added other sources such as Census information and death reports from the Social Security Administration. Data are available starting from 2011.

Five of the partners linked their data with information from a regional database on homelessness to better understand how often people in the county experiencing homelessness used medical services and what health conditions they had. Partners have also worked with health insurers, the Centers for Medicare & Medicaid Services, and disease-specific organizations to link patient data in the network to information about healthcare services they received outside the network or more detailed information on disease symptoms and results of health care that patients experience.

Population (as of 03/31/19)


  • 57% white
  • 19% black
  • 15% Hispanic


  • 58% female
  • 42% male


  • 18% 20 years or younger
  • 31% 21–44 years
  • 30% 45–64 years
  • 12% 65–74 years
  • 8% 75+ years

How is the network supporting research?

While a Partner Network in PCORnet, CAPriCORN completed 34 research studies. CAPriCORN also partnered with Patient-Powered Research Networks, or PPRNs, to write research proposals and provide data on certain types of patients. PPRNs are operated and governed by patient groups and their partners and are focused on particular conditions or populations.

How does the network support future research?

CAPriCORN developed a sliding scale fee for researchers who want to use the network’s database. These fees help cover the network’s costs. The network continues to format its data to follow the Common Data Model and involve patients and healthcare providers in planning and carrying out research studies. CAPriCORN also takes part in research with other networks in PCORnet and builds relationships outside of PCORnet.


Clinical Data Research Networks (CDRN): CDRNs are networks that originate in healthcare systems, such as hospitals, health plans, or practice-based networks, and securely collect health information during the routine course of patient care.

Common Data Model (CDM): A CDM establishes a standard way of defining and formatting data.

PCORnet: PCORnet is a network of networks that brings together patients, clinicians, researchers, and healthcare systems to share information and participate in research.

Journal Citations

Project Information

Abel Kho, MD^
Northwestern University
$8,780,309 *

Key Dates

March 2019

Study Registration Information

^The original Principal Investigator for this project was Terry Mazany, MA, MBA, at the Chicago Community Trust.

Journal Articles


Has Results
State State The state where the project originates, or where the primary institution or organization is located. View Glossary
Last updated: January 27, 2023