Cochran's Q Test is a statistical method used to determine if there are significant differences in proportions across multiple related groups. It is particularly useful when dealing with binary outcomes, such as success/failure or yes/no responses, and is often applied in studies with repeated measures or matched subjects. The test evaluates whether the observed frequencies of outcomes differ significantly from what would be expected if there were no differences among the groups. If the test yields a significant result, it suggests that at least one group differs from the others, prompting further investigation into the specific differences.