What is a population based case-control study?

A population-based case-control study is one in which the cases come from a precisely defined population, such as a fixed geographic area, and the controls are sampled directly from the same population.

What is a case based case-control study?

A case-control study is designed to help determine if an exposure is associated with an outcome (i.e., disease or condition of interest). In theory, the case-control study can be described simply. First, identify the cases (a group known to have the outcome) and the controls (a group known to be free of the outcome).

What are the elements of case-control study?

Five steps in conducting a case-control study

Define a study population (source of cases and controls)
Define and select cases.
Define and select controls.
Measure exposure.
Estimate disease risk associated with exposure.
Confounding factors.
Matching.
Bias.

What are the advantages of case-control studies?

Advantages: They are efficient for rare diseases or diseases with a long latency period between exposure and disease manifestation. They are less costly and less time-consuming; they are advantageous when exposure data is expensive or hard to obtain.

How many controls are in a case-control study?

Investigators planning case-control studies are usual- ly advised to include no more than four or five controls per case because little statistical power is gained by fur- ther increasing this ratio (1,2).

How is case-control study done?

In a case-control study, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups.

What is difference between Case-control and cohort study?

Whereas the cohort study is concerned with frequency of disease in exposed and non-exposed individuals, the case-control study is concerned with the frequency and amount of exposure in subjects with a specific disease (cases) and people without the disease (controls).

What are limitations of case-control studies?

The main limitations of case-control studies are:

‘Recall bias’ When people answer questions about their previous exposure to certain risk factors their ability to recall may be unreliable.
Cause and effect.
‘Sampling bias’
Other limitations.

Why are case-control studies good?

If a disease occurs very infrequently, one would have to follow a large group of people for a long period of time to accrue enough incident cases to study. Such use of resources may be impractical, so a case-control study can be useful for identifying current cases and evaluating historical associated factors.

What are the advantages and disadvantages of case control studies?

Advantages and Disadvantages of Case-Control Studies. Advantages: They are efficient for rare diseases or diseases with a long latency period between exposure and disease manifestation. They are less costly and less time-consuming; they are advantageous when exposure data is expensive or hard to obtain.

What are the types of case control studies?

The two types of case-control studies are: Non-matched case-control study: this is the simplest form. Find a person with the disease and enroll them in the study. Then enroll a control and determine their exposure status. Matched case-control: Find a person with the disease and enroll them in the study.

What is case control study vs cohort?

A cohort study is a research design where the researcher studies a group of people, also known as a cohort, for a longer period of time. On the other hand, a case-control study is a research design used by researchers where the research begins with an outcome to comprehend the cause.

What is a cohort or case control study?

Cohort Study: A cohort study is a research design where the researcher studies a group of people also known as a cohort for a longer period of time. Case-Control Study: A case-control study is a research design used by researchers where the research begins with an outcome to comprehend the cause.

What is a population based case-control study? A population-based case-control study is one in which the cases come from a precisely defined population, such as a fixed geographic area, and the controls are sampled directly from the same population. What is a case based case-control study? A case-control study is designed to help determine if…