In a hypothetical study, the investigator wants to look at the association between exposure to pesticides in the workplace and t
he development of asthma. The investigator selects a large group of individuals who work on PLTW farms across the country and follow them over ten years to determine who develops asthma. Of the 318 individuals exposed to pesticides, 69 develop asthma. 990 individuals worked in areas that were free of exposure to pesticides. 903 are asthma-free after ten years. Required:
Is the hypothetical study a prospective or retrospective cohort study? Explain your answer.
Prospective cohort study is a type of observational study in epidemiology, where the subjects of the study are followed and monitored by the researcher over time, so as to investigate their risk or susceptibility to the disease. This is unlike the retrospective study where the researcher refers back in time to archived data.
The experiment described above is a prospective cohort study because the researcher follows the participants (the workers) over a span of time (ten years). At the end, he tried to evaluate the association between the exposure to the pesticide and the disease.
