Research

1.How do we establish cause-effect (causal) relationships in research? What criteria should be met to have evidence of a causal relationship?  (1 paragraph)
2.Discuss why the RCT is considered the gold standard in research evidence? (1 paragraph)
3.Describe the type of study in the Tison et al. 2020 paper. What are the limitations of this type of study?  Could this study be re-designed to increase the level of evidence? (1-2 paragraphs)