A study designed to observe events that have already occurred.
A study of data from the past. Case-control study.
An inquiry planned to observe events that have already occurred (a case-control study is usually retrospective) compare with a prospective study which is planned to observe events that have not yet occurred.
A backward-looking review of the characteristics of a group of individuals in relation to morbidity, embracing some aspects of cross-sectional and/or case control studies. The term is sometimes loosely used as a synonym for such studies.
The opposite of a prospective study, involvying review of the casenotes and/or interviewing or sending a questionnaire to a collection of people (often those who have been diagnosed with the same condition) to assess the effects of the illness, that is its morbidity. The procedure is commonly used in studying the epidemiology of disease. It is regarded as likely to provide less reliable results than a prospective study, in which patients are recruited when they first come to the researcher’s or doctor’s attention.
A clinical study in which patients or their records are investigated after the patients have experienced the disease, condition, or treatment.
A research project that collects data and draws conclusions from events that have already occurred.