Investigation generally used to test possible causes of a disease or disorder, in which persons with and without a designated disorder are compared with respect to prior or current exposure to a putative agent or causal factor. Often these types of studies are referred to as retrospective studies because the logic of the study design leads from effect to cause. For example, patients with hepatitis C (cases) and without hepatitis C (controls) are compared with respect to their exposure to blood products.
A study in which the risk factors of people with a disease are compared with the risk factors of those without a disease. For example, in the Carolina Breast Cancer Study, women with breast cancer were compared to women without breast cancer to determine if they had different risk factors in their lives (for example, pesticide exposure) that may have increased their risk of getting breast cancer.
involves identifying subjects with a clinical condition (cases) and subjects free from the condition (controls), and investigating if the two groups have similar or different exposures to risk indicator(s) of factor(s) associated with the disease.
Study in which the involved subjects refer to the presence (case) or the absence (controls) of the disease in question. The information collected refers to the last exposition of cases and controls.
A study comparing persons with a given condition or disease (the cases) and persons without the condition or disease (the controls) with respect to antecedent factors. (See also: Retrospective Studies.)
This might be considered a randomized controlled trial played backwards. People who get sick or have a bad outcome are identified and "matched" with people who did better. Then, the effects of the therapy or harmful exposure which might have been administered at the start of the trial are evaluated. In other words, you first find the people who did poorly and then look at the therapy or exposure and compare it to people who didn't get the therapy. Needless to say, this is a crude way of doing a study. When the effect of interest is HARM, this may actually be the only ethical way of doing the study.
a retrospective, analytical, observational study often based on secondary data in which the proportion of cases with a potential risk factor are compared to the proportion of controls (individuals without the disease) with the same risk factor
a type of cross-sectional study used in medicine
a type of observational analytic study in which subjects are selected on the basis of whether they have (cases) or do not have (controls) a particular disease under study
a type of population study in which people with a condition, such as heart attack, are compared to people without that condition
retrospective study for examining factors contributing to a disease.
A study in which people with a disease or condition (cases) are compared to another group of people from the same population who don't have that disease or condition (controls). In this way risk factors for developing the disease or condition can be identified.
epidemiology study that uses a sample group of people rather than the entire population. It compares characteristics of those with birth defects (cases) and those without (controls). The key question is: Does a specific exposure occur more in cases than in controls
One type of epidemiological study. Two groups, the cases (those with the disease being studied) and the controls (a comparison group) are compared to each other. Often used to investigate comparatively rare diseases.
A study design in which patients with and without a certain outcome are identified and then compared with respect to an exposure variable of interest.
Retrospective comparison of exposures of persons with disease (cases) with those of persons without the disease (controls) ( see Retrospective study). ( Harm)
a retrospective observational study in which investigators identify a group of patients with a specified outcome (cases) and a group of patients without the specified outcome (controls). Investigators then compare the histories of the cases and the controls to determine the extent to which each was exposed to the intervention of interest.
a study which involves identifying people ("cases") who have DVT and comparing their recent travel histories and medical backgrounds with a closely matched series of "control" subjects without DVT
A type of observational analytic study. Enrollment into the study is based on presence (``case'') or absence (``control'') of disease. Characteristics such as previous exposure are then compared between cases and controls.
An epidemiologic study that examines selected patients who have a defined disease (cases) with persons without the disease (controls).
A type of study that involves identifying patients who have the outcome of interest (cases) and patients who have not (controls), and looking back to see if they had the exposure of interest.
A study that compares two groups of people: those with the disease or condition under study (cases) and a very similar group of people who do not have the disease or condition (controls). Researchers study the medical and lifestyle histories of the people in each group to learn what factors may be associated with the disease or condition. Also called a retrospective study.
Study groups are defined on the basis of disease (or outcome) status. The frequency of the risk factor (exposure) in the cases (diseased) is compared with the frequency of the risk factor (exposure) in the controls (nondiseased).
A study designed to investigate whether a particular exposure (for example, exposure to an industrial pollutant) is associated with an outcome (for example, a particular type of cancer). First, the researchers identify the cases (people known to have the outcome) and the controls (people free of the outcome). Second, they look back in time to find out which people in each group had the exposure. Third, they compare the frequency of the exposure in the cases to that in the controls.
An epidemiologic study in which one collects a group of people with a certain disease (cases) to compare with another group of people without that disease (controls) to see if some factor (suspected of being a cause) is more common in the disease group. Most important is the fact that people must already have the disease to be chosen as cases. The outcome is expressed as an 'odds ratio'.
(Syn: case-referent study, case comparison study) A type of observational analytical study. Enrolment in the study is based on the presence ("case'') or absence ("control'') of a disease of interest. Histories of previous exposures to some suspected risk factor(s) are then compared between cases and controls, controlling for potential "confounders." Causal factors should occur more frequently among cases than among controls.
Compares people with a disease or condition ('cases') to another group of people from the same population who don't have that disease or condition ('control's'). A case-control study can identify risks and trends, and suggest some possible causes for disease, or for particular outcomes.
An inquiry in which groups of individuals are selected in terms of whether they do (the cases) or do not (the controls) have the disease of which the etiology is to be studied, and the groups are then compared with respect to existing or past characteristics judged to be of possible relevance to the etiology of the disease.
(see Appendix N) An observational study in which the past history of exposure to a suspected risk factor (eg therapy involving the proposed drug) is compared proposed drug between cases (who have the outcome or disease) and controls (who resemble the cases but do not have the or outcomed disease).
A systematic comparison of troublesome persons, places, times, or events to untroublesome ones to find out the characteristics that might cause the problem. This type of study is particularly useful when troublesome cases are a very small proportion of all cases 17, 32, 33
(CASE-REFERENT OR CASE-COMPARISON STUDY). Study generally used to test possible causes of a disease or disorder, in which individuals who have a designated disorder are compared with individuals who do not have the disorder with respect to previous current exposure to a putative causal factor. For example, persons with hepatic cancer (cases) are compared with persons without hepatic cancer (controls) and history of hepatitis B is determined for the two groups. A CASE-CONTROL STUDY is often referred to as a RETROSPECTIVE STUDY (even if patients are recruited prospectively) because the logic of the design leads from effect to cause.
a study in which the risk factors of people who have been diagnosed with a disease are compared with those without the disease. Because the risk factor (e.g., nutrient intake) is generally measured at the time of diagnosis, it is difficult to determine whether the risk factor was present prior to the development of the disease. Another potential draw back is the difficulty in obtaining well-matched control subjects.
An observational study that begins with patient cases who have the outcome or disease being investigated and control subjects who do not have the outcome or disease and then looks backward to identify possible precursors or risk factors.
involves identifying patients who have the outcome of interest (cases) and control patients without the same outcome, and looking back to see if they had the exposure of interest. See also glossary of study designs.
an epidemiological study in which a group of, say, cancer patients (cases) is compared to a similar but cancer-free population (controls) to help establish whether the past or recent history of a specific exposure such as smoking, alcohol consumption and dietary intake, etc. are causally related to the risk of disease.
An epidemiologic study contrasting those with the disease of interest (cases) to those without the disease (controls). The groups are then compared with respect to exposure history, to ascertain whether they differ in the proportion exposed to the chemical(s) under investigation.