Answer:
Dr. Edward is using a longitudinal research design.
Dr. Janice is using a cross-sectional research design.
Step-by-step explanation:
A longitudinal study also known as longitudinal research design is a type of study in which repeated observations are made on a particular set of variables (e.g. same individuals) over a long or short period of time.
On the other hand, a cross-sectional study also known as cross-sectional research design is a type of study in which observations are made on different variables (e.g. different people) at the same time.