The chi-square test of independence is a statistical method used to determine if there is a significant association between two categorical variables. It compares the observed frequencies in each category to the frequencies expected if the variables were independent. A higher chi-square value indicates a stronger relationship between the variables. To perform the test, researchers create a contingency table that displays the frequency counts for each combination of the variables. The test calculates the chi-square statistic, which is then compared to a critical value from the chi-square distribution to assess significance, typically using a significance level of 0.05.