Numerical Data Interpretation Flashcards

A line graph shows patient satisfaction scores increasing from 68% in January to 82% in June. What is the percentage point increase?

Answer: 14 pp

82% − 68% = 14 percentage points increase over the period.

A table shows drug adverse-event rates: Drug X = 8 per 1,000 patients, Drug Y = 12 per 1,000 patients. What is the ratio of Drug X's rate to Drug Y's rate in simplest form?

Answer: 2:3

8:12 simplifies to 2:3 by dividing both values by 4.

A hospital's length of stay data shows: mean = 5.2 days, median = 4.0 days. What does the difference between mean and median suggest about the data?

Answer: The data is skewed by some very long stays

A mean much higher than the median indicates positive skew, suggesting a few patients with very long stays are pulling the mean up.

A scatter plot shows a strong positive correlation between handwashing compliance (%) and patient-acquired infection rates. Which interpretation is correct?

Answer: Higher compliance is associated with more infections

A strong positive correlation means higher compliance is associated with higher infection rates — the question states a positive correlation, so both variables move in the same direction.

Clinical trial data shows that a new drug reduced systolic blood pressure by an average of 12 mmHg with a 95% confidence interval of 10–14 mmHg. What does the confidence interval indicate?

Answer: We are 95% confident the true population effect lies between 10 and 14 mmHg

A 95% confidence interval means that if the study were repeated many times, 95% of such intervals would contain the true population effect.

A table shows 4 hospitals' readmission rates. Hospital A: 9%, B: 11%, C: 8%, D: 14%. What is the range of readmission rates?

Answer: 6 pp

Range = highest − lowest = 14% − 8% = 6 percentage points.