A physiotherapy department measures pain scores on a 0 to 10 scale in 30 patients before starting a new exercise programme and again after 8 weeks in the same patients. The score changes are approximately normally distributed. Which test is most appropriate to assess whether the programme changed pain scores?
- A Paired t-test ✓
- B Independent samples t-test
- C Chi-square test
- D One-way ANOVA
Correct answer: A. Paired t-test
Explanation
The same 30 subjects are measured twice, producing paired observations, and the differences are normally distributed, so the paired t-test applied to individual change scores is the correct choice. An independent samples t-test would be appropriate only if different patients formed the before and after groups, and it would wrongly ignore the within-subject pairing, losing statistical power.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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