Dr. Bloom conducted a "cross-sectional study".
A cross-sectional study analyzes the connection between malady (or other wellbeing related state) and different factors of enthusiasm as they exist in a characterized populace at a solitary point in time or over a brief time frame.
Cross-sectional studies can be thought of as giving a preview of the recurrence of a sickness or other wellbeing related attributes (e.g. introduction factors) in a populace at a given point in time. Cross-sectional investigations are utilized to survey the weight of sickness or wellbeing needs of a populace and are especially helpful in educating the arranging and designation of wellbeing assets.