Cohort Discovery (i2b2)

i2b2 enables researchers to determine counts of patients using data from EHR systems.  Through a point-and-click interface, researchers can define cohorts of patients using de-identified data from both Epic and Allscripts without the need for IRB approval.

Once an investigator has defined the cohort of interest, s/he can, with IRB approval, obtain a list of MRNs for the patients in question.

Researchers can use i2b2 to answer questions like:

  • “How many patients have a history of colon cancer using ICD-9 codes 153.* and 154.*?"
  • “How many patients with colon cancer were younger than age 50 at the time of initial diagnosis?”
  • “How many patients with colon cancer had a colectomy procedure performed and then were admitted to the hospital within 30 days?”

i2b2 Training

Interested in learning how to use i2b2?

Online training is available in the LMS; just look for the "Introduction to i2b2" course. If you need help booking a course in the LMS, follow these instructions

In-person workshops are held on the last Thursday of every month at the Library Surface Hub from 11am to 12:30pm. More info is available at



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