Health informatics is a multidisciplinary field that uses health information technology (HIT) to improve health care via any combination of higher quality, higher efficiency, and new opportunities. Information and communication technology tools are integral to all areas of health care. HIT deals with the resources, devices, and methods required to optimize the acquisition, storage, retrieval, and use of information in health. One of the fundamental elements is the use of integrated data repositories. Types of data repositories include operational data stores (ODSs), clinical data warehouses, clinical data marts, and clinical registries.

Clinical Research Informatics (CRI) is a subfield of health informatics that tries to improve the efficiency of clinical research by using informatics methods. Some of the problems tackled by CRI are: creation of data warehouses of healthcare data that can be used for research, support of data collection in clinical trials by the use of electronic data capture systems, streamlining ethical approvals and renewals, and/or maintenance of repositories of past clinical trial data.