A short introduction to terms used when reading research. Definitions are general; a paper may specify a narrower meaning for its own methods.
Peptide
A molecule made from amino-acid units joined by peptide bonds.
Mechanism
A proposed or observed process that could explain an effect.
Endpoint
A defined observation or measurement used to assess a study question.
Control
A comparison condition used to interpret an experimental result.
In vitro
Research performed outside an intact living organism, such as in a cell-culture model.
In vivo
Research performed in a living organism. The organism and model matter.
Clinical study
Research involving human participants; the design, population and endpoints still need to be examined.
Replication
Repeating or independently testing a finding to assess whether it holds under specified conditions.
Limitation
A feature of a study that constrains what can reasonably be concluded from its results.