Statistical significance versus public health significance: which statement correctly distinguishes them?

• A. Statistical significance relates to p-values and confidence intervals.
• B. Public health significance relates to the practical impact on policy decisions.
• C. Statistical significance relates to p-values and confidence intervals; public health significance relates to the real-world impact.
• D. Public health significance is about the sample size.

Answer: (C)

Statistical significance is about whether an observed effect is likely not due to chance, usually assessed with p-values and confidence intervals. Public health significance asks whether the size and importance of that effect matter in the real world—will it meaningfully change health outcomes, policy decisions, or resource use? The best statement captures both ideas: statistical significance relates to p-values and confidence intervals, while public health significance relates to the real-world impact. The other options fall short because they either focus only on one side or misattribute public health significance to factors like sample size, which affects precision and power but not the practical importance of the finding.