The prospective study design studies the impact of a phenomenon, situation, program, attitude or problem in the future. Most of the studies that are conducted using the prospective study design are also classified as experimental studies since the aim of the investigator is to wait for the impact of a program or a situation to see the results on the target population. Unlike retrospective studies the prospective studies uses experiments in the field or laboratory to explore the outcomes later on. The outcomes that are established as a result of these study findings can then be generalized for the future happenings of the same kind.
Characteristics of prospective study design
- Prospective studies usually take a cohort of sample and study them for long period of time to establish facts.
- The target sample should not be lost before the outcomes are established otherwise the study will become biased.
- These studies are usually conducted on a sufficient number of audience to prove the statistical significance of the outcomes.
- Prospective studies are more reliable and generalizable than the retrospective studies.
- The follow up of the possible outcomes can be done using any method like questionnaire, face to face interviews, phone interviews, lab exams etc.
- Sometimes these studies prove very useful in answering questions that the investigator did not imagine to get answers. In the course of time the investigator can understand several other factors other than the one he is studying.
- The cost of conducting such studies is always higher than the retrospective studies and case studies
Example of prospective study design
A prospective cohort study was conducted on the role of depression on the development and persistence of adult obesity. The investigator selected a group of adolescent students, did some assessment at baseline and than follow up was done after 1 year. The investigator assessed both obesity and depression in adolescents at baseline. It was concluded that baseline depression is highly significant cause of the development and persistence of obesity in adolescents. It is a known fact that obesity also cause depression so prevention and treatment of both disorders at early age was concluded to be necessary.