Can odds ratio be used in cohort study?

Can odds ratio be used in cohort study?

Key Concept: Remember that in a cohort study you can calculate either a risk ratio or an odds ratio, but In a case-control study: you can only calculate an odds ratio.

Can we use odds ratio in cross-sectional studies?

Odds ratio (OR) and risk ratio (RR) are two commonly used measures of association reported in research studies. In cross-sectional studies, the odds ratio is also referred to as the prevalence odds ratio (POR) when prevalent cases are included, and, instead of the RR, the prevalence ratio (PR) is calculated.

What is the difference between a cohort and cross-sectional study?

Cohort studies are used to study incidence, causes, and prognosis. Because they measure events in chronological order they can be used to distinguish between cause and effect. Cross sectional studies are used to determine prevalence.

Can a cohort study be cross-sectional?

The cross-sectional cohort design involves cross-sectional sampling to obtain a study cohort and then retrospective assessment of the history of exposures and outcomes in the members of that cohort.

What measure of association is best for cross-sectional studies?

For chronic disease studies or studies of long-lasting risk factors, POR is the preferred measure of association in cross-sectional studies. For acute disease studies, PR is the preferred measure of association. If the prevalence of disease is low, i.e. 10% or less in exposed and unexposed populations, POR = PR.

What evidence level is a cross sectional study?

Cross sectional study designs and case series form the lowest level of the aetiology hierarchy. In the cross sectional design, data concerning each subject is often recorded at one point in time. For instance, a questionnaire might be sent to a district where forestry is a predominant industry.

Can a study be cross sectional and case-control?

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.

Why are odds ratios not used in cross sectional studies?

Odds ratios calculations are possible and valid in cohort, case-control and cross-sectional designs, but the OR is often not the estimate that is desired or is less efficient than alternatives. 1) Cross-sectional studies often want to estimate prevalence, so a relative measure such as OR wouldn’t make sense if prevalence is your goal.

Do you think the odds ratio can be used for cross..?

A ratio between two prevalences to analyse the association in a cross-sectional study is also a rate ratio but it is not a “relative risk” because a cross-sectional study is a point study where you see all the elements at the same time so it is not possible to talk about causality. We can not talk about exposure and outcome.

How is the cohort and cross sectional study calculated?

The Cohort and Cross-Sectional study calculates the sample size recommended for a study given a set of parameters and the desired confidence level.

When to use odds ratios in case control?

Quick reference can be made to Bhopal’s Concepts of Epidemiology 2nd edition (Ch. 9). Odds ratios calculations are possible and valid in cohort, case-control and cross-sectional designs, but the OR is often not the estimate that is desired or is less efficient than alternatives.