Final answer:
The most likely source for a clinical data warehouse is electronic health records, as they contain comprehensive patient data used to improve healthcare quality.
Step-by-step explanation:
The most likely source of data for a clinical data warehouse is a. Electronic health records (EHRs). EHRs are comprehensive, digital versions of patients' paper charts and contain a patient's medical history, diagnoses, medications, treatment plans, immunization dates, allergies, radiology images, and laboratory test results. The sharing of digital records among health providers is one method proposed to improve the quality and reduce the cost of health care in the U.S. while ensuring patient privacy. Clinical data warehouses aggregate such data from EHRs to facilitate clinical research, performance monitoring, and improving healthcare delivery.