Does statistical significance equal clinical significance?

• A. Yes; they are interchangeable concepts.
• B. Not necessarily; significance relates to probability, not clinical importance.
• C. Statistical significance is always greater than clinical significance.
• D. No; statistical significance does not imply clinical significance.

Answer: (D)

Statistical significance is about how likely the observed result could occur by chance if there is no real effect. It speaks to probability, not to how important the finding is in real patient care. A result can be statistically significant even if the actual difference is tiny and not clinically meaningful, especially in large studies where small effects are easy to detect. On the other hand, a clinically important difference might not reach statistical significance in a small or noisy study, even though it would matter in practice.

To judge clinical significance, look at the size and precision of the effect (for example, absolute risk difference, relative risk, or number needed to treat) and whether that magnitude crosses a minimal clinically important difference. Consider the confidence interval around the estimate and practical factors like safety, cost, and patient values. In short, significance relates to probability; clinical significance relates to real-world impact.