How do you select cases in a case-control study?

Selection of the Controls
  1. The comparison group (“controls”) should be representative of the source population that produced the cases.
  2. The “controls” must be sampled in a way that is independent of the exposure, meaning that their selection should not be more (or less) likely if they have the exposure of interest.

Is a case study the same as a case-control study?

A case report is the description of the clinical story of a single patient, whereas a case-control study compares 2 groups of participants differing in outcome in order to determine if a suspected exposure in their past caused that difference.

What type of research is a case-control study?

A case-control study is a type of observational study commonly used to look at factors associated with diseases or outcomes. The case-control study starts with a group of cases, which are the individuals who have the outcome of interest.

What is case-control study PDF?

A case–control study involves the identification of individuals with (‘cases’) and without (‘controls’) a particular disease or condition. The prevalence (or level) of exposure to a factor is then measured in each group.

Is a case-control study cross sectional?

Cross sectional studies are used to determine prevalence. They are relatively quick and easy but do not permit distinction between cause and effect. Case controlled studies compare groups retrospectively. They seek to identify possible predictors of outcome and are useful for studying rare diseases or outcomes.

Is case-control study quantitative or qualitative?

In a health care context, randomised controlled trials are quantitative in nature, as are case-control and cohort studies. Surveys (questionnaires) are usually quantitative .

What are the advantages of case-control studies?

Advantages
  • Easy to conduct as no follow up is required.
  • No attrition, as no follow up is needed.
  • Gives faster results.
  • Inexpensive.
  • Suitable for rare and newly identified diseases.
  • More than one risk factors can be studied simultaneously.
  • Ethical problem lesser as disease has already occurred.

Is case-control study longitudinal?

Case-control studies for longitudinal data bring about economies in cost and time when the disease is rare and when assessing the exposure level of risk factors is difficult. We propose a way of using an ordinary logistic model to analyse case-control longitudinal data.

What is a case-control study choose the correct answer below?

Choose the correct answer below. Case-control studies are observational studies that are​ retrospective, meaning that they require individuals to look back in time or require the researcher to look at existing records.

What is the difference between case-control study 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).

Are case-control studies cross sectional or longitudinal?

Cross sectional studies are used to determine prevalence. They are relatively quick and easy but do not permit distinction between cause and effect. Case controlled studies compare groups retrospectively. They seek to identify possible predictors of outcome and are useful for studying rare diseases or outcomes.

Which of the following is the best description of a case-control study?

A case-control study is a retrospective study that looks back in time to find the relative risk between a specific exposure (e.g. second hand tobacco smoke) and an outcome (e.g. cancer). A control group of people who do not have the disease or who did not experience the event is used for comparison.

How many controls are in a case?

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).

Are case-control studies experimental or observational?

Cohort studies and case control studies are two types of observational studies. Cohort study: For research purposes, a cohort is any group of people who are linked in some way.

What is the difference between RCT and case-control study?

Case–control studies are observational in nature and thus do not provide the same level of evidence as randomized controlled trials. The results may be confounded by other factors, to the extent of giving the opposite answer to better studies. … Case–control studies are therefore placed low in the hierarchy of evidence.

Can case-control studies determine causality?

Although case–control studies are an efficient method for the study of rare outcomes, there are important limitations inherent to this design. Like other observational studies, associations measured in case–control studies may or may not represent causal relationships.