Question

1. Doctors are starting to see the presentation of individuals in their 30s and 40s that had relatively mild COVID-19 symptoms experiencing strokes. Some present to the ER after weathering most of the infection at home, and others present with death.

1. A cross-sectional study
2. A retrospective cohort study
3. A cohort study
4. A case-control study
5. An ecologic study

Answer 1

The doctors starting a retrospective cohort study in this case,In retrospective studies are a type of the observational reserch in which the investigater look back in time at archived or self report data to examine whether the risk of disease was different between exposed and non exposed patients,and in this studies look at data that already exist and try to identify risk factors for particular condition. That determines the current status of the disease or outcome in the paticipants to be observed if the patient having mild symptoms of COVID-19.