Service Description

USC, CHLA and DHS research teams can use the research data warehouse for study planning (feasibility assessments, power analyses) through their respective i2b2 portals. The self-service website allows researchers to query de-identified patient data residing in the research data warehouse. For example, find the number of patients at CHLA that meet study inclusion and exclusion criteria. With the help of the CRI team, users can also extract identifiable patient information for screening or recruitment purposes with the proper IRB approval to do so. Once the warehouse data has been validated for quality, research teams will be able to perform large-scale analyses on the data already existing in the warehouse (e.g., epidemiology studies).

How to get access
CHLA researchers are required to complete Human Subjects and HIPAA training. For more information on how to complete the required training, please email or refer the CHLA Investigator’s manual. Once complete, and reflecting in your iStar profile, simply email requesting access to CHLA i2b2.

Benefits for users

  • Sample Size Planning / Feasibility Assessment: Determine how many patients in the USC, CHLA or DHS electronic health records meet your study criteria. View distributions of patients based on gender, race, and age.
  • Recruitment or Chart Screening: Use i2b2 to define a set of patients to consider for your study. Then, outside of i2b2, work with the health system(s) to access MRN or contact information. IRB approval is required for identified data sets.
  • Outcomes Research: Submit a data request for de-identified data for retrospective analysis
Request the service


Self-Service data requests fulfilled through i2b2 are free of charge For more complex data requests requiring the re-identification of Patient Health Information, or data unavailable through i2b2 rates can be found here.

Frequently Asked Questions

The service infrastructure consists of both centralized support staff and embedded staff at CHLA. Embedded staff members are familiar with local practices, policies, and workflows and serve as informatics liaisons between the research community and the clinical operations community.

IRB approval is required whenever a researcher is requesting information beyond aggregate patient counts or outside of *limited data sets. Please explicitly state in your IRB application and or amendment the use of i2b2 and all of the data elements requested. For example, if requesting MRN, phone and medication orders, this must be clearly stated and approved in your IRB application and or amendment. Alternatively, you may run your query in i2b2, submit an i2b2 data request and attach that data request number generated by the system in your IRB application or amendment. For more clarification regarding your specific request, please email to set a time to review your scenario.

* A limited dataset is a dataset at the patient level, with all 18 HIPAA identifiers removed or obscured. In this scenario the completion of a Data Use Agreement is required for the release of information.

Contact information

CHLA i2b2
Clinical Research Informatics

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Tooltip: Clinical Trial Management System (CTMS)

USC’s Clinical Trial Management System, OnCore, is a jointly sponsored, web-based software system for managing clinical trials.

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NIH Funding Acknowledgment: Important - All publications resulting from the utilization of SC CTSI resources are required to credit the SC CTSI grant by including the NIH funding acknowledgment and must comply with the NIH Public Access Policy.