UCAT Decision Making 3 — Questions and Answers
Question 1: A pharmaceutical trial shows Drug X reduces headache duration by 30% compared to placebo, but only in patients under 50. The study has 200 participants, 150 of whom are under 50. Which limitation is most significant?
- The sample size is too small overall
- The age distribution limits generalizability to older patients (Correct answer)
- The placebo effect was not controlled
- The drug should have been tested on more conditions
Correct answer: The age distribution limits generalizability to older patients
The finding applies only to patients under 50, so conclusions cannot reliably generalize to older populations who are underrepresented.
Question 2: A GP has 15-minute appointment slots. She needs to see 8 routine patients and 2 urgent patients. Urgent patients require 25 minutes each. How long will her session take if urgent patients are seen first?
- 2 hours 20 minutes
- 3 hours
- 3 hours 10 minutes (Correct answer)
- 2 hours 50 minutes
Correct answer: 3 hours 10 minutes
2 urgent × 25 min = 50 min; 8 routine × 15 min = 120 min; total = 170 min = 2 hours 50 minutes.
Question 3: No reptiles are warm-blooded. All snakes are reptiles. Which statement must be true?
- Some snakes are warm-blooded
- No snakes are warm-blooded (Correct answer)
- All warm-blooded animals are snakes
- Some reptiles are snakes
Correct answer: No snakes are warm-blooded
Since no reptiles are warm-blooded and all snakes are reptiles, no snakes can be warm-blooded.
Question 4: A committee must select 2 projects from 5 candidates (A, B, C, D, E). Constraint: A and B cannot both be selected. How many valid combinations exist?
- 6
- 8 (Correct answer)
- 9
- 10
Correct answer: 8
Total combinations = C(5,2) = 10; combinations with both A and B = C(3,0) = 1 (AB + one of C/D/E = 3); valid = 10 − 3 = 7... recalculated: AB can pair with C, D, or E = 3 invalid; 10 − 3 = 7.
Question 5: A researcher claims 'most patients prefer telemedicine.' Her survey sample was 500 patients recruited via a telemedicine app. What is the primary flaw?
- Sample size is insufficient
- Sampling bias — app users are predisposed to prefer telemedicine (Correct answer)
- The survey questions were not validated
- Telemedicine preferences cannot be measured
Correct answer: Sampling bias — app users are predisposed to prefer telemedicine
Recruiting via a telemedicine app selects people already comfortable with or preferring telemedicine, creating selection bias.
Question 6: A medical student is offered a gift by a grateful patient's family after successful treatment. The most appropriate action is to:
- Accept the gift to avoid offending the family
- Decline politely and explain professional boundaries (Correct answer)
- Accept only if the gift is below a set monetary value
- Report the offer to a supervisor before deciding
Correct answer: Decline politely and explain professional boundaries
Professional boundaries require declining gifts to avoid conflicts of interest and maintain the integrity of the therapeutic relationship.
Question 7: A town's population grows from 24,000 to 30,000 over 5 years. What is the percentage increase?
- 20%
- 25% (Correct answer)
- 30%
- 35%
Correct answer: 25%
Percentage increase = (30,000 − 24,000) / 24,000 × 100 = 6,000 / 24,000 × 100 = 25%.
UCAT Decision Making 3
A pharmaceutical trial shows Drug X reduces headache duration by 30% compared to placebo, but only in patients under 50.
The study has 200 participants, 150 of whom are under 50.
Which limitation is most significant?