In a case-control study examining smoking and lung cancer, 150 out of 200 cases are smokers, while 100 out of 400 controls are smokers. Calculate the odds ratio (OR) for smoking as a risk factor for lung cancer.

You are conducting a stratified sample of 1,000 participants from a population of 10,000 divided into two strata: 30% men and 70% women. How many men should be included in the final sample?

What is one major advantage of a cohort study over a case-control study?

A study is conducted to test a new intervention for controlling blood glucose levels. Out of 150 participants, 50 were randomly assigned to the intervention group, and 100 to the control group. The intervention group showed a mean reduction of 15 mg/dL in blood glucose, with a standard deviation of 5 mg/dL. The control group showed a mean reduction of 10 mg/dL, with a standard deviation of 7 mg/dL. Calculate the effect size using Cohen’s d.

What is the main purpose of randomization in clinical trials?

A study reports that there were 419 patients with a particular genetic disorder and 59 deaths between 1998 and 2013. What is the case fatality rate, expressed as a percentage?

Which of the following is a key characteristic of an observational study?

What is the key difference between association and causality when considering confounders?

Questions on Dialogues of Plato

For questions (8) – (9), please discuss the significance and meaning of EACH of the following quotations in a well-formed paragraph.