Glossary | The Cochrane Collaboration (worth bookmarking)

examples:

Adverse effect search for term

An adverse event for which the causal relation between the drug/intervention and the event is at least a reasonable possibility. The term ‘adverse effect’ applies to all interventions, while ‘adverse drug reaction’ (ADR) is used only with drugs. In the case of drugs an adverse effect tends to be seen from the point of view of the drug and an adverse reaction is seen from the point of view of the patient.See also: Adverse event, Side effect Also called: Adverse reaction

Baseline characteristics search for term

Values of demographic, clinical and other variables collected for each participant at the beginning of a trial, before the intervention is administered.

Causal effect search for term

An association between two characteristics that can be demonstrated to be due to cause and effect, i.e. a change in one causes the change in the other. Causality can be demonstrated by experimental studies such as controlled trials (for example, that an experimental intervention causes a reduction in mortality). However, causality can often not be determined from an observational study.