Available clinical data include patient demographics, data collected during health care encounters (in-patient admissions, offices visits, emergency department visits, surgical procedures, telemedicine, etc.), diagnoses, procedures, documentation flowsheets, lab values, medications, and clinical notes. Electronic Health Record (EHR) data are pulled from Epic. Community Health Center (CHC) data are pulled from OCHIN (a different version of Epic used by a national network of community health centers).

In addition to data from Epic and OCHIN, the CDW includes data from various data systems that are no longer in active clinical use (legacy systems). These legacy systems include PICIS (operating room data), IBEX (emergency department data), SDK (patient registration data), SCM (inpatient EHR data), Logician (outpatient EHR data), and EWS/IDX (patient scheduling data). Legacy systems are not actively maintained; data from them can be cumbersome to extract and are not monitored for quality.

Data are collected and consolidated into the CDW on a regular schedule, but not in real-time. Data from many of the systems that contribute to the CDW can be cross-referenced or linked using unique patient identifiers.