Biostatistics & Research · single question
A chart shows the relationship between vitamin C and periodontitis (parameter D: OR=1.8, CI 3.5-3.9, p<0.01). What is the interpretation?
Show answer and explanation
Correct answer: A. Strong association, statistically significant
- A. Parameter D: OR = 1.8, CI 3.5-3.9, p <0.01. Interpretation: An OR of 1.8 represents a STRONG association (compared to OR=1 for null). The 95% CI (3.5-3.9) does NOT include 1 and p<0.01 confirms STATISTICAL SIGNIFICANCE. The narrow CI indicates a precise estimate. Therefore: STRONG association, statistically significant. ⚠️ Comparing to other parameters (A=1.8/1.5-7.5, B=3.7/0-7, C=4.1/1-6.4) — Parameter D has the smallest CI, making it the most precise.
- B. P<0.01 confirms statistical significance — 'not statistically significant' is incorrect.
- C. OR of 1.8 represents a MODERATE association. The CI (3.5-3.9) is narrow and does not include 1, confirming statistical significance. However, OR of 1.8 may be considered 'weak-to-moderate' by some interpretations.
- D. P<0.01 = statistically significant. This option is doubly incorrect.
Practice Biostatistics & Research questions Biostatistics & Research study notes