What is a follow up study?
Definition. A follow-up study, more commonly called a cohort study, has three basic components: exposure, time, and outcome. The cohort is followed over time to determine development of the outcome. To determine incidence of the outcome, subjects who have the outcome at baseline are excluded.
What is a prospective follow up study?
A prospective study watches for outcomes, such as the development of a disease, during the study period and relates this to other factors such as suspected risk or protection factor(s). The study usually involves taking a cohort of subjects and watching them over a long period.
What is an example of a prospective study?
Famous Prospective Study Examples. The Framingham Heart Study is one example of a prospective cohort study; The researchers have, to date, studied three generations of Framingham residents in order to understand the causes of heart disease and stroke.
Is a prospective cohort study quantitative?
As the name suggests, quantitative refers to a group of methods whose main focus is on quantities, that is, numbers. In a health care context, randomised controlled trials are quantitative in nature, as are case-control and cohort studies. Surveys (questionnaires) are usually quantitative .
When would you use a prospective cohort study?
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).
What level is a prospective cohort study?
Table 3
| Level | Type of evidence |
|---|---|
| II | Lesser quality prospective cohort, retrospective cohort study, untreated controls from an RCT, or systematic review of these studies |
| III | Case-control study or systematic review of these studies |
| IV | Case series |
What type of study is a prospective cohort study?
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.
How do you create a prospective cohort study?
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 types of study designs are there?
Types of Study Designs
- Meta-Analysis. A way of combining data from many different research studies.
- Systematic Review.
- Randomized Controlled Trial.
- Cohort Study (Prospective Observational Study)
- Case-control Study.
- Cross-sectional study.
- Case Reports and Series.
- Ideas, Editorials, Opinions.
What is the difference between a cohort study and a case-control 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 is an example of a case-control study?
For example, in a case-control study of the association between smoking and lung cancer the inclusion of controls being treated for a condition related to smoking (e.g. chronic bronchitis) may result in an underestimate of the strength of the association between exposure (smoking) and outcome.
What’s the difference between cross sectional and cohort 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.
Which is better case control or cohort studies?
Retrospective cohort studies are NOT the same as case-control studies. In retrospective cohort studies, the exposure and outcomes have already happened. Therefore, cohort studies are good for assessing prognosis, risk factors and harm. The outcome measure in cohort studies is usually a risk ratio / relative risk (RR).
What is being compared in a cohort study design?
The cohort study design identifies a people exposed to a particular factor and a comparison group that was not exposed to that factor and measures and compares the incidence of disease in the two groups.
What is a cohort study in statistics?
Statistics Definitions > Cohort Study. A Cohort study, used in the medical fields and social sciences, is an observational study used to estimate how often disease or life events happen in a certain population. “Life events” might include: incidence rate, relative risk or absolute risk.
What is exposure in cohort study?
In a cohort study, a group of individuals exposed to a putative risk factor and a group who are unexposed to the risk factor are followed over time (often years) to determine the occurrence of disease. The incidence of disease in the exposed group is compared with the incidence of disease in the unexposed group.
Which measure of disease frequency is computed in Cohort Study?
However, in a cohort study participants may be lost during follow-up. To account for these variations during follow up, a more precise measure can be calculated, the incidence rate . Incidence rates also measure the frequency of new cases of disease in a population.
What are the measures of frequency?
When measuring disease frequency, proportions and rates are very helpful when comparing groups, because they relate the number of people with disease to the size of the population in which they occur. Prevalence and incidence are the two fundamental measures of disease frequency.
What is measure of frequency in statistics?
A frequency is the number of times a data value occurs. For example, if ten students score 80 in statistics, then the score of 80 has a frequency of 10. Frequency is often represented by the letter f.
What is the formula to find frequency?
The formula for frequency is: f (frequency) = 1 / T (period). f = c / λ = wave speed c (m/s) / wavelength λ (m).
What are the 3 types of frequency distributions?
There are three types of frequency distributions. Categorical frequency distributions, group frequency distributions and on group frequency distributions.
How do I find the frequency in statistics?
Count the tally marks to determine the frequency of each class. The relative frequency of a data class is the percentage of data elements in that class. The relative frequency can be calculated using the formula fi=fn f i = f n , where f is the absolute frequency and n is the sum of all frequencies.