https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6409129/

a. What is the population?

b. The variables- How difficult are these variables to measure? Are these variables qualitative or quantitative?

c. Is this an observational study or an experiment?

d. Is this a sample survey? If so, does any of the wording of the survey encourage bias? Explain.

e. What is the sample? How big is the sample?

f. How was the sample selected? Do you see any possibility of bias in the sampling process? Explain.

g. If this is study involves an experiment, what are the control subjects and the experimental subjects?

h. What are some sample statistics from the study? Are they reasonably presented?

i. Do the results of the study make sense? Explain.