In a study to identify risk factors for multiple sclerosis (MS), researchers use hospital records to identify 25 people with MS and 25 people without MS then interview them about childhood exposures to pesticides and other chemicals. What type of study is this?

Respuesta :

Answer: It is called retrospective study

Explanation:

A retrospective study uses existing data that have been recorded for reasons other than research. A retrospective case series is the description of a group of cases with a new or unusual disease or treatment.