A study that began in 2010 reported the incidence of heart attacks in a group of college alumni. Researchers wanted to study risk factors for heart attack. The alumni completed a questionnaire in 2010 that asked about their physical activity at baseline and then were followed until 2020. The investigators found that there were 330 heart attacks in 76,000 person-years of observation among alumni who reported that they regularly climbed 50 or more stairs per day, and 220 heart attacks in 38,000 person-years of observation among alumni who reported that they regularly climbed fewer than 50 stairs per day in 2010.

Based on the description above, please answer the following questions:

(a) Identify the study design and describe how you know that is the study design

(b) What the two appropriate measures of association that can you calculate from these data? List, calculate, and interpret two (2) measures of association that can be calculated from this data:

i. (1) Measure of association, point estimate for measure, and interpretation

ii. (2) Measure of association, point estimate for measure, and interpretation