Pearson’s Chi-square test of Independence

  • Assumption to check: .

    • Independence of observations

  • Report on design in Methods section

    • Report on variables

    • Name the statistical package or program used in the analysis

  • Report statistics in Results section: Chi-square statistic, degrees of freedom, number of samples, p-value

  • Example:

    • Method section: The Pearson’s Chi-squared test was used to determine the association between smoking and the occurrence of cancer. The analysis was performed in R software (RRID:SCR_001905)

    • Results section: The Pearson chi-square test of independence detected a significant association between smoking and the presence of cancer (χ2(1, N = 200) = 46.7, p < .001). The odds ratio was 9.52 (95% CI [4.76, 19.06]), indicating that someone is 9.5 times more likely to develop cancer if they are a smoker.