retrospective study

retrospective study,

a study in which a search is made for a relationship between one (usually current) phenomenon or condition and another that occurred in the past. An example is a study of the family histories of young women diagnosed as having clear cell adenomas of the vagina, which yielded a relationship between the administration of diethylstilbestrol to the mothers of the women during pregnancy and the development of the condition in the daughters. See also case-control study.

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retrospective study,

a study in which a search is made for a relationship between one phenomenon or condition and another that occurred in the past (e.g., the exposure to toxic agents and the rate of occurrence of disease in the exposed group compared with a control group not exposed).

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study

a scholarly examination. Specific types of study are also detailed under blind, case-control, cohort, cross-sectional.

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analytical study

one in which a phenomenon is described and an attempt made to analyze the effects of variables on the phenomenon.

descriptive study

one in which a phenomenon is described but no attempt is made to analyze the effects of variables on the phenomenon.

follow-up study

one carried out to find out whether there has been change in the situation since the initial study.

longitudinal study

one carried out over a period of time so that chronological time has an opportunity to exert an effect as a variable.

observational study

see descriptive study (above).

prospective study

one in which the data to be studied are yet to be generated, the events having not yet occurred.

retrospective study

one based on examination of existing data, on events that have already occurred.

simulation study

one in which the real circumstances are simulated, either in fact, or by means of a set of mathematical formulae each of which expresses the probability of each outcome in a series of consequential events that mirror the possible pathways in a real-life situation.

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retrospective study

Case-control study Epidemiology An epidemiologic study that analyzes data collected before a certain point in time, to determine if past events are related to the present distribution of disease; a study–eg, case control study in which investigators select groups of Pts who have already been treated and analyze data from the events experienced by these Pts. Cf Prospective study.