Watson-Glaser Critical Thinking Appraisal Glaser Interpretation 1 — Questions and Answers
Question 1: A university library recorded that students who borrowed physical books at least twice per month earned final grades averaging 0.4 GPA points higher than students who never borrowed books. The library did not track whether high-achieving students were simply more likely to use the library regardless of books. Which of the following interpretations is BEST supported by the passage?
- Borrowing physical books causes students to earn higher grades.
- There is an association between frequent book borrowing and higher GPA, though causation has not been established. (Correct answer)
- Students who borrow books are more intelligent than those who do not.
- Universities should require all students to borrow books monthly to improve academic performance.
Correct answer: There is an association between frequent book borrowing and higher GPA, though causation has not been established.
The passage describes a correlation between book borrowing frequency and GPA but explicitly notes that the direction of causation is unknown — high achievers may simply use the library more. Option B accurately reflects an association without claiming causation. Option A overstates by asserting causation. Options C and D introduce conclusions that go far beyond what the data support.
Question 2: A regional hospital introduced mandatory hand-hygiene check-ins for all staff in 2023. Over the following 12 months, hospital-acquired infection (HAI) rates fell from 4.2 per 1,000 patient-days to 2.8 per 1,000 patient-days. No other major infection-control policy changed during that period. Which interpretation follows BEYOND A REASONABLE DOUBT from the data above?
- The hand-hygiene program was the sole cause of the decline in HAI rates.
- HAI rates at this hospital were lower in the 12 months after the program launched than in the 12 months before. (Correct answer)
- All hospitals that adopt mandatory hand-hygiene programs will see similar reductions in HAI rates.
- The hospital's hand-hygiene compliance rate reached 100% during the study period.
Correct answer: HAI rates at this hospital were lower in the 12 months after the program launched than in the 12 months before.
The only conclusion the data directly support is that HAI rates were measurably lower in the period following the program's introduction — that is a straightforward factual comparison stated in the passage. Option A claims sole causation, which requires ruling out all confounds. Options C and D extend the finding beyond this hospital and introduce unverified details about compliance, neither of which the passage addresses.
Question 3: A survey of 2,400 adults found that people who reported sleeping fewer than six hours per night were 2.3 times more likely to describe their overall health as 'poor' compared with adults who slept seven to nine hours. The survey relied entirely on self-reported data. Which of the following is the MOST accurate interpretation of these findings?
- Sleeping fewer than six hours per night directly damages physical health.
- Self-reported short sleep duration is associated with a higher likelihood of self-reported poor health in this sample. (Correct answer)
- Adults who sleep less are choosing an unhealthy lifestyle.
- Seven to nine hours of sleep is the medically optimal range for all adults.
Correct answer: Self-reported short sleep duration is associated with a higher likelihood of self-reported poor health in this sample.
Because both variables — sleep duration and health status — were self-reported, the most defensible interpretation is that the two self-reported measures are associated within this sample. Option A asserts direct causation that the survey design cannot establish. Option C attributes causation to personal choice, and Option D converts a statistical association into a universal medical prescription, both of which go beyond the evidence.
Question 4: A municipal government planted 1,200 additional trees along residential streets over two years. A follow-up study found that summer surface temperatures in those neighborhoods dropped by an average of 2°C compared to similar neighborhoods without new plantings. Researchers noted that wealthier neighborhoods received more trees. Which interpretation is NOT justified by the passage?
- Surface temperatures were lower in neighborhoods that received new trees than in comparable neighborhoods that did not.
- The tree-planting program may have delivered unequal benefits across income levels.
- Planting trees is the most cost-effective strategy a city can use to reduce urban heat. (Correct answer)
- The data suggest a link between increased urban tree coverage and reduced surface temperatures.
Correct answer: Planting trees is the most cost-effective strategy a city can use to reduce urban heat.
Options A, B, and D are each directly supported by the passage: A restates the temperature finding, B is supported by the note about wealthier neighborhoods receiving more trees, and D draws a reasonable inferential link. Option C introduces a cost-effectiveness comparison that the passage never makes — no cost data are provided and no alternative strategies are evaluated, making this claim unjustified.
Question 5: An employer replaced its annual performance reviews with quarterly check-ins. After 18 months, voluntary employee turnover fell from 22% to 14%. Employee engagement scores, measured by a third-party survey, rose by 11 percentage points over the same period. Which of the following conclusions can be drawn with the MOST confidence from this information?
- Quarterly check-ins are superior to annual reviews in every industry.
- Both voluntary turnover and engagement scores improved during the period when quarterly check-ins were in use. (Correct answer)
- Employees universally prefer more frequent feedback from managers.
- The company's profitability increased as a result of reduced turnover.
Correct answer: Both voluntary turnover and engagement scores improved during the period when quarterly check-ins were in use.
The passage confirms two measurable changes during the 18-month period: turnover fell and engagement scores rose. Option B simply and accurately summarizes these facts. Option A generalizes to all industries without evidence. Option C claims a universal employee preference that is not stated. Option D introduces profitability data that the passage never mentions.
Question 6: A nonprofit literacy program reported that children who participated in its eight-week summer reading initiative read an average of 14 books over the summer, compared to an average of 4 books for non-participants. Participation was voluntary, and parents of participants were required to provide weekly reading logs. Which of the following interpretations is BEST supported by the passage?
- The program caused participants to read more books than non-participants over the summer.
- Participants read more books on average than non-participants, though self-selection and parental involvement may explain part of the difference. (Correct answer)
- Non-participating children are less interested in reading than participating children.
- The program should be made mandatory to close the reading gap between participants and non-participants.
Correct answer: Participants read more books on average than non-participants, though self-selection and parental involvement may explain part of the difference.
Option B correctly captures the observable gap (14 vs. 4 books) while acknowledging that voluntary enrollment and required parental logging create selection effects — families who opted in may already be more reading-oriented. Option A asserts that the program caused the difference without accounting for these confounds. Option C draws an inference about interest that the data do not establish. Option D prescribes a policy change that goes well beyond the evidence.
Watson-Glaser Critical Thinking Appraisal Glaser Interpretation 1
A university library recorded that students who borrowed physical books at least twice per month earned final grades averaging 0.4 GPA points higher than students who never borrowed books.
The library did not track whether high-achieving students were simply more likely to use the library regardless of books.
Which of the following interpretations is BEST supported by the passage?