Which of the following is true about imaginary friends?
a. They are a sign of serious pathology.
b. They are extremely rare.
c. As many as 65 percent of preschoolers have them.
d. They are more common in later-born children.
Question 2
Dr. Klein wants to investigate the long-term effects of antidepressants in children. To do so, she randomly selects a group of subjects and follows them across five years. What type of study is this?
a. naturalistic c. cross-sectional
b. cross-sequential d. longitudinal
