User:Nswetenham/Case-crossover study

Case-crossover study

A case-crossover study is a type of research study in which people who have experienced a particular outcome (cases) are asked about their exposure to a suspected risk factor at the time of the event and during a control period where no event occurred. This study design is used to study transient effects.

Example: people who have experienced a myocardial infarction (heart attack) are asked about what medicines they took on the day of the heart attack and on another day where no heart attack occurred.

before and after exposures are compared in people who have experienced a particular outcome (cases).