A pharmaceutical company claims their new drug is MORE effective than the existing standard. To test this claim statistically, which type of test is most appropriate?
- A One-tailed test (upper tail) ✓
- B One-tailed test (lower tail)
- C Two-tailed test
- D Either one-tailed or two-tailed gives the same result
Correct answer: A. One-tailed test (upper tail)
Explanation
When the alternative hypothesis specifies a direction, such as the new drug being more effective, a one-tailed test in the upper tail is appropriate. A two-tailed test is used when the hypothesis is non-directional, simply testing for any difference. Using a two-tailed test for a directional claim would be unnecessarily conservative and less powerful.
Reference: Bessmans Biostatistics for Public Health, 2nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.