This glossary includes over 4,000 terms and acronyms related to clinical research. The definitions are meant to be understood in the clinical research context. For example, the term "study" is assumed to mean "clinical research study". (In most cases, the term "study" is used rather than the term "trial.") The definitions are obviously intended to be accurate; however, in the interest of clarity and brevity, fine points may be excluded. In some cases, the specific source or context of a term, e.g., "(FDA)", is provided at the end of the definition. CDISC, ICH and caBIG definitions are provided verbatim in their original format and identified as to their source in the form [Source].