Interpreting Evidence and Data Flashcards
7 cards from real Watson-Glaser Critical Thinking Appraisal practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Interpreting Evidence and Data flashcards as text
A hospital advertises a 95% survival rate for its cardiac surgery patients. A competing hospital advertises 90%. Which piece of information is most critical before concluding the first hospital is better?
Answer: Whether the case mix (severity of patients) differs between the hospitals
A hospital that treats more high-risk patients may have a lower survival rate even if it performs equally well or better.
A longitudinal study tracks 500 smokers and 500 non-smokers for 20 years and finds smokers have significantly higher rates of lung disease. This study design best supports which type of conclusion?
Answer: A strong causal link is plausible, though experimental proof requires a randomized trial
Longitudinal observational studies can strongly suggest causation but cannot definitively prove it the way a randomized controlled trial can.
Sales data shows that umbrella purchases spike every April. An analyst claims umbrellas are suddenly more popular in spring. What alternative explanation should be considered?
Answer: Seasonal rainfall in April drives umbrella purchases rather than a change in popularity
Seasonal weather patterns, not a shift in consumer preferences, most plausibly explain the recurring April spike.
A report presents the median household income as $65,000 and the mean as $95,000 in the same dataset. What does this discrepancy most likely indicate?
Answer: A small number of very high earners are pulling the mean above the median
When the mean substantially exceeds the median, it typically signals a right-skewed distribution caused by high-value outliers.
An experiment finds that a new fertilizer increases crop yield by 15% in greenhouse conditions. A farmer plans to apply it immediately at scale. What interpretive caution is most important?
Answer: Greenhouse results may not generalize to outdoor field conditions with different soil, weather, and pests
Controlled laboratory or greenhouse conditions often differ substantially from real-world environments, limiting the direct applicability of findings.
A dataset shows that countries with higher chocolate consumption win more Nobel Prizes per capita. The best interpretation is:
Answer: Both variables correlate with a third factor, such as national wealth or research investment
Wealthier nations tend to both consume more chocolate and invest more in scientific research, making wealth the likely confounding variable.
A graph shows that every year a researcher has published a paper, the stock market has risen. The researcher claims their publications predict market gains. This reasoning is flawed because:
Answer: Coincidental co-occurrence of two independent events does not establish prediction or causation
Two variables moving together over a small number of cases can easily be coincidental, especially without a plausible mechanism.