An investigator samples a group of clients from a clinic based on their disease status—in particular, whether or not they have HTN. Of the 250 people sampled, 40% were found to have HTN. Knowing their disease status, a questionnaire is administered to the people in the study to determine how many have a family history (FHx) of stroke (in a first-degree relative). Of the people without HTN, 8% had a FHx of stroke. Of the people with HTN, 37% had a FHx of stroke. Create a 2 × 2 table using this information and answer the following questions.
• What type of study design is this?
• Can you calculate RR (relative risk) using these data? Why or why not?
• Can you calculate OR (odds ratio) using these data?
• Calculate the correct descriptive statistic for this study (either RR or OR).
• What is the correct interpretation of the statistic used?
a. Patients with a FHx of stroke are 6.75 times more likely to develop HTN than patients with no FHx of stroke. b. Patients with HTN are 6.75 times more likely to have a FHx of stroke than those with normal blood pressure
• What are possible errors that could be made in this type of study?