In Order to Investigate Whether Nutritional Information Combined with Telephone

Multiple Choice

In order to investigate whether nutritional information combined with telephone counseling is better at increasing weight loss among women who are obese than telephone counseling alone, researchers randomly assign one group of obese women to the counseling only group and assign another group of obsess women to the counseling plus nutritional information group. What type of epidemiological study is this?

A) Cross sectional study
B) Retrospective cohort study
C) Case-control study
D) Randomized trial