4. Vaping has become a major concern and you decide to investigate how prevalent it is in your community of 10,000 people. After some discussion with experts in the respiratory field, you decide to estimate the prevalence to within 4 percentage points of the true population prevalence, with 95% confidence.

i. A journal article reported the prevalence of vaping in another country (similar population characteristics) as 5.2%. How many students (n) must you recruit? Please show your calculations (6 marks)

a. 599 persons would be recruited to estimate the prevalence of vaping in the community

b. 125 persons would be recruited to estimate the prevalence of vaping in the community

c. 118 persons would be recruited to estimate the prevalence of vaping in the community

d. 108 persons would be recruited to estimate the prevalence of vaping in the community

ii. How many participants will you need to recruit if previous studies in your country typically report a 5% non-response rate. Please show your calculations (4 marks) a. 631 participants b. 124 participants c. 132 participants d. 114 participants

iii. To implement the study, which ONE of the following would be the BEST study design and WHY? (3 marks)

a. Cohort Study b. Case-Control Study c. Cross-Sectional Study d. Randomised Control Trial

iv. Which ONE of the following sampling strategies would be BEST for recruiting the participants and WHY? (3 marks)

a. Systematic Random Sample b. Cluster Sampling c. Snowball Sampling d. Quota Sampling