Questions: The Harvard Heart Letter reported on a study that examined the diets of 1226 older women over 15 years. They discovered that the more vegetables the women consumed, the lower their risk of dying of cardiovascular disease. From this study can we conclude that eating a diet high in vegetables prevents cardiovascular disease? Why or why not? Choose the correct answer below. A. No. This is an observational study. B. Yes. This is an observational study. C. No. This is a controlled experiment. D. Yes. This is a controlled experiment.

The Harvard Heart Letter reported on a study that examined the diets of 1226 older women over 15 years. They discovered that the more vegetables the women consumed, the lower their risk of dying of cardiovascular disease. From this study can we conclude that eating a diet high in vegetables prevents cardiovascular disease? Why or why not?

Choose the correct answer below.
A. No. This is an observational study.
B. Yes. This is an observational study.
C. No. This is a controlled experiment.
D. Yes. This is a controlled experiment.

Transcript text: The Harvard Heart Letter reported on a study that examined the diets of 1226 older women over 15 years. They discovered that the more vegetables the women consumed, the lower their risk of dying of cardiovascular disease. From this study can we conclude that eating a diet high in vegetables prevents cardiovascular disease? Why or why not? Choose the correct answer below. A. No. This is an observational study. B. Yes. This is an observational study. C. No. This is a controlled experiment. D. Yes. This is a controlled experiment.

Solution

Solution Steps

Step 1: Identify the type of study

The study described is an observational study because it examines the diets of 1226 older women over 15 years without actively intervening or assigning treatments.

Step 2: Understand the limitations of observational studies

Observational studies can identify associations between variables (e.g., vegetable consumption and cardiovascular disease risk), but they cannot establish causation. This is because confounding factors may influence the results.

Step 3: Evaluate the conclusion

Since the study is observational, we cannot conclude that eating a diet high in vegetables prevents cardiovascular disease. It only shows a correlation, not causation.

Step 4: Select the correct answer

The correct answer is: A. No. This is an observational study.