- Amino acid
- A molecular building block that can be linked with others to form peptides and proteins.
- Peptide
- A short chain of amino acids joined by peptide bonds.
- Sequence
- The order of amino acids in a peptide or protein.
- Formulation
- The specific preparation of a substance, including its ingredients and physical form.
- In vitro
- Research performed outside an organism, for example in cultured cells.
- Preclinical
- Research conducted before clinical testing, often using laboratory systems or animal models.
- Mechanism
- A proposed or demonstrated explanation of how an effect occurs.
- Clinical outcome
- A result measured in people, such as symptoms, function or an event relevant to health.
- Observational study
- A study that examines exposures or outcomes without assigning the intervention or exposure of interest.
- Randomized trial
- A study that uses chance to assign participants to comparison groups.
- Comparator
- The condition or group against which another is evaluated.
- Surrogate measure
- A measurement used in place of an outcome of direct interest. Its relevance needs evidence.
- Confounding
- A distortion that can arise when another factor is related to both the exposure and the outcome.
- Generalizability
- How far a study’s findings may apply beyond the people and conditions that were studied.
- Adverse event
- An unfavorable event observed during research or treatment; timing alone does not prove causation.
- Systematic review
- A review using explicit methods to identify, assess and synthesize relevant research.
Further reading: NHGRI peptide glossary →, NHGRI amino acid glossary →, NIH study-design introduction → and AHRQ trial-methods guidance →. These introductory definitions are editorial drafts.
