McNemar's Test Calculator

Your details

Use exact binomial when the total number of discordant pairs (b + c) is less than 25. Continuity correction (Edwards) improves the chi-square approximation for small samples.
The threshold below which the p-value is considered statistically significant.
Number of pairs where both the first and second measurement were positive (yes). These concordant pairs do not affect the test statistic.
Discordant pairs where the first measurement was positive and the second was negative. These pairs drive the test.
Discordant pairs where the first measurement was negative and the second was positive. These pairs drive the test.
Number of pairs where both measurements were negative (no). These concordant pairs do not affect the test statistic.
Chi-square statisticSignificant (p < 0.05)
4.5676

McNemar chi-square with 1 degree of freedom (or continuity-corrected version)

P-value (two-sided)0.0326
Significant?Yes (p = 0.0326 < 0.05)
Discordant pairs (b + c)37
Odds ratio (b/c)0.48
Difference in proportions (b - c) / n0.13
95% CI for difference0.0135 to 0.2465
Proportion 1 (before/case)0.42
Proportion 2 (after/control)0.55
Proportion 1 (before)0.42
Proportion 2 (after)0.55
Difference (change)0.13

The change is statistically significant (p = 0.0326).

  • The McNemar chi-square statistic is 4.5676 with 1 degree of freedom.
  • More pairs changed from negative to positive (c = 25) than from positive to negative (b = 12), suggesting an increase in the proportion.
  • The odds ratio for discordant pairs is 0.480, meaning b is 0.48x as common as c.

Next stepReport the chi-square statistic, degrees of freedom (1), p-value, and the 95% confidence interval for the difference in proportions. Consider the clinical or practical significance alongside the statistical result.

 = Powered by OnlyCalculators