A chart shows the relationship between vitamin A deficiency and periodontitis, with an odds ratio of 4.1, 95% CI of 1.4-6.4, and p-value < 0.0001. What does this data suggest?

Interpretation: (1) Odds ratio of 4.1 — an OR > 1.0 indicates a positive association between vitamin A deficiency and periodontitis; an OR of 4.1 means those with vitamin A deficiency have 4.1 times the odds of periodontitis compared to those without deficiency. An OR of 4.1 is considered a strong association (OR > 3.0 is generally considered strong). (2) 95% CI of 1.4-6.4 — the CI does not include 1.0 (the null value), confirming statistical significance. (3) p < 0.0001 — this extremely small p-value confirms that the result is highly statistically significant. Therefore: strong association, statistically significant.