How do you determine statistical significance in a study?

Correct answer: A. P-value (probability value)

• A. CORRECT — The p-value (probability value) is the standard tool for determining statistical significance. A p-value < 0.05 (alpha) indicates the result is statistically significant, meaning less than 5% probability the result occurred by chance.
• B. INCORRECT — Standard deviation measures data variability/spread around the mean; it is descriptive, not directly a significance test.
• C. INCORRECT — The correlation coefficient (r) measures the strength and direction of an association between two variables; it does not by itself determine statistical significance.
• D. INCORRECT — Confidence intervals provide a range of plausible values for a parameter but technically complement rather than replace the p-value for determining significance.