1. Explain why external validity is important if you are conducting a study on the effectiveness of aspirin in persons who are in the midst of having a stroke. You can give an example to explain the situation. Do not define external validity to apply the concept to the study.
2. What are possible problems when recruiting participants for a study using the Internet?
3. What is meant by meta analysis? Find an article that has conducted a meta analysis.
4. Explain the advantage of having conducted a meta analysis in the study you selected.