1. Match each study design to their appropriate characteristics.

A. Particularly prone to selection bias and information bias

B. Ideal for rare outcomes

C. Prone to the ecological fallacy

D. Appropriate for estimating prevalence in a population

E. Uses groups instead of individual participants

1. Cross-sectional

2. Case-control

3. Ecological

2. A study examined the association between physician prescribing practices and opioid use disorder. Individuals with opioid use disorder were identified via medical records among four large health systems in Massachusetts. Individuals without opiod use disorder were randomly selected from medical records among the same health systems. What type of study design is described?

A. Cross-sectional

B. None of the above

C. Case-control

D. Ecological

3. Researchers examined the impact of helmet laws on fatalities among motorcyclists across states in the U.S. What type of study is this?

A. Cross-sectional

B. None of the above

C. Case-control

D. Ecological