Humanities Homework Help

I’m stuck on a Psychology question and need an explanation.

read article and answer questions 

1. What made this study design (the method they used to collect data) strong?

2. In the first part of the article, the authors review previous studies and their findings. What were two interesting findings/results from the previous studies?

3. What were some of the results from the study?

4. How could this study have been better?