In a clinical trial comparing a new antihypertensive with placebo, the absolute risk of cardiovascular events was 12% in the placebo group and 6% in the treatment group. The Number Needed to Treat (NNT) is:

• A 8
• B 12
• C 20
• D 17 ✓

Explanation

ARR = 12% − 6% = 6% = 0.06. NNT = 1/ARR = 1/0.06 = 16.7, rounded to 17. NNT represents the number of patients who need to be treated to prevent one additional adverse outcome. Relative risk reduction = 6/12 = 50%, but NNT uses absolute risk reduction.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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