Definition (Cross sectional study): It is the simplest form of an observation study. It is based on single examination of a cross section of population at one point in time. It is also known as prevalence study. This study is more useful for chronic than short lived disease. It has been linked to a photograph & provides information about disease prevalence.
For example: In a study of hypertension. We can also collect data during the survey about age, sex, physical exercise, body weight and other variable interst.
- Based on a sample of general population.
- Relatively short time period is required.
- Relatively low cost.
- Ethically safe.
- Cheap and simple.
- Cause and effect relationship cannot be measured.
- Disease of long duration will have higher proportion of case.
- Provides very little information about natural history of disease.
- Persons under the treatment may not present evidence of disease at the time of study.