Hard - Quiz 1

Evaluate study designs at their limits: weigh internal versus external validity, catch subtle biases, and distinguish statistical significance from real-world importance.

Question 1 of 5

0 of 5 answered Score: 0%

Question 1

Researchers conduct a tightly controlled lab experiment with 80 college students to test whether background music affects reading comprehension. Students are randomly assigned to silence or music conditions. The music group scores significantly lower. Which of the following best describes the study's strengths and limitations?

🔒 Answer question 1 to unlock

A hospital administrator notices that Hospital A has a higher overall surgery survival rate than Hospital B. However, when the data is separated by surgery type (minor and major), Hospital B has a higher survival rate for both minor surgeries and major surgeries. Which of the following best explains this apparent contradiction?

🔒 Answer question 2 to unlock

A tech company reports that users of its study app score 15% higher on practice tests than non-users. The data comes from comparing users who chose to download the app with students who did not. What is the most significant threat to the validity of this claim?

🔒 Answer question 3 to unlock

A university randomly assigns 200 student volunteers to either a meditation program or a wait-list control group. After 8 weeks, the meditation group reports significantly lower anxiety. Which conclusion is most appropriate?

🔒 Answer question 4 to unlock

A pharmaceutical company tests a new allergy medication and reports that the treatment group showed "statistically significant improvement" over the placebo group (\(p = 0.03\)). The average symptom score improved by 0.5 points on a 100-point scale. A doctor reviewing the study says the result may not be meaningful. What is the best justification for the doctor's concern?

correct answers

Did you find this quiz useful?