SCENARO: A health researcher wanted to analyze data on binge drinking among college undergraduates using data collected from the prior year by staff at the Student Health Center from 300 students. Students seeking non-emergency care and who were feeling well enough were asked to take a brief anonymous survey using an electronic tablet while they waited in the waiting room to see a doctor. The original primary research question when the data were collected was: What is the rate of binge drinking among undergraduate students at the college?

The health researcher's new primary research question for his analysis with the same data was: What is the association between race and ethnicity and rates of binge drinking among college undergraduates?

QUESTION: In the described scenario, the investigators tried to measure stress and levels of stress. What is the difference between these two concepts, and how valid is the instrument used to measure them?

NOTE: The question was asked as part of our class discussion, but I am confused because stress can also be classified based on its nature. Physical stress refers to actual physical activities and events that wreak havoc on the human body. As for the instrument used to measure stress and levels of stress, I couldn't find specific information about the instrument used in your scenario.