A research study that follows
over time groups of individuals who are alike in many ways
but differ by a certain characteristic (for example, female nurses who smoke and those who do not smoke) and compares them for a particular outcome (such as lung cancer).
When would you use a cohort study?
A cohort study identifies
a group of people
and follows them over a period of time. The aim is to look at how a group of people are exposed to different risk factors which may affect their lives. Cohort studies can look at many different aspects of people’s lives, including their health and/or social factors.
What are prospective cohort studies used for?
A prospective cohort study is a longitudinal cohort study that follows over time a group of similar individuals (cohorts) who differ with respect to certain factors under study,
to determine how these factors affect rates of a certain outcome
.
What is an example of a prospective cohort study?
A prospective cohort study takes
a group of similar people (a cohort) and studies them over time
. … For example, a cohort of thirty-year-old people in a certain town might be studied to see who develops lung cancer. Half of the cohort might be smokers and half may not. This enables comparisons between the two groups.
Why are prospective cohort studies good?
A prospective cohort study design is
ranked higher in the hierarchy of evidence
than a retrospective design because the outcome, predictor, and confounding variables can be better measured and controlled.
What is an example of a cohort?
The term “cohort” refers to a group of people who have been included in a study by an event that is based on the definition decided by the researcher. For example, a cohort of people born in Mumbai in the year 1980. This will be called a “birth cohort.” Another example of the cohort will be
people who smoke
.
What are the characteristics of a cohort study?
The characteristic feature of a cohort study is that
the investigator identifies subjects at a point in time when they do not have the outcome of interest and compares the incidence of the outcome of interest among groups of exposed
and unexposed (or less exposed) subjects.
What is an example of a cohort study?
One famous example of a cohort study is
the Nurses’ Health Study
, a large, long-running analysis of women’s health, originally set up in 1976 to investigate the potential long term consequences of the use of oral contraceptives.
What are the types of cohort studies?
There are two types of cohort studies:
Prospective and Retrospective
. The two groups of cohorts (exposed and un-exposed) are followed prospectively over time to track the development of new disease.
Is a cohort 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 defines a cohort study?
A cohort study is a particular form of longitudinal study that samples a cohort (
a group of people who share a defining characteristic
, typically those who experienced a common event in a selected period, such as birth or graduation), performing a cross-section at intervals through time.
How do you conduct a prospective cohort study?
- Identify the study subjects; i.e. the cohort population.
- Obtain baseline data on the exposure; measure the exposure at the start. …
- Select a sub-classification of the cohort—the unexposed control cohort—to be the comparison group.
- Follow up; measure the outcomes using records, interviews or examinations.
What is an example of a prospective study?
Prospective Cohort Studies: … The Framingham Heart Study,
the Nurses Health Study
, and the Black Women’s Health Study are good examples of large, productive prospective cohort studies. In each of these studies, the investigators wanted to study risk factors for common chronic diseases.
Is prospective cohort study good?
Observational studies in general and cohort studies in specific are a good source of information when an experiment is not feasible. Prospective cohort studies
provide valuable information when studying the relationship between exposure and outcome
.
What are the pros and cons of using a prospective cohort study?
Because prospective studies are designed with specific data collection methods, it has the advantage of
being tailored to collect specific exposure data and may be more complete
. The disadvantage of a prospective cohort study may be the long follow-up period while waiting for events or diseases to occur.
Are cohort studies good for rare diseases?
As with prospective cohort studies,
they are not good for very rare diseases
. If one uses records that were not designed for the study, the available data may be of poor quality. There is frequently an absence of data on potential confounding factors if the data was recorded in the past.
