Choosing the Appropriate Statistical Test: Marge Funk, PhD, RN Bivariate Statistical Tests Measurement Test Name or Purpose Related IV DV Parametric Tests Independent t-test I Test the difference between 2 N I/R independent group means Paired t-test R Test the difference between 2 related N I/R group means 1-way analysis of I Test the difference the means of N I/R variance (ANOVA) 3+ independent groups Repeated measures R Test the difference among the means N I/R ANOVA of 3+ related groups or sets of scores Pearson correlation I, R Test the existence of a relationship I/R I/R between 2 variables Linear regression -- Predict of DV for given value of IV I/R I/R Nonparametric Mann-Whitney U-test I Test the difference in of scores of N O 2 independent groups Wilcoxon signed-rank R Test the difference in ranks of scores N O test of 2 related groups Kruskal-Wallis test I Test the difference in ranks of scores N O of 3+ independent groups Friedman test R Test the difference in ranks of scores N O of 3+ related groups Chi square test I Test the difference in proportions in N N 2+ independent groups McNemar test R Test the difference in proportions for 2 N N related groups (2x2) Cochran’s Q test R Test the difference in proportions for N N 3+ related groups Fisher’s test I Test the difference in proportions in 2 N N independent groups when N < 30, any expected cell frequency < 5, or cell with observed frequency of 0 Phi coefficient or odds I Examine the magnitude of a N N ratio relationship between 2 dichotomous variables Cramer’s V I Examine the magnitude of a N N relationship between 2 variables (not restricted to dichotomous) Spearman’s rho I, R Test the existence of relationship O O between 2 variables IV, Independent variable; DV, dependent variable; I, independent; R, related; N, nominal; O, ordinal or non-normally distributed interval/ratio; I/R, interval/ratio. Note: On some tests, the measurement level of the IV & DV can be switched. Multivariate/Multivariable & Advanced Statistical Tests
Choosing the Appropriate Statistical Test: Marge Funk, PhD, RN Bivariate Statistical Tests Test Name or Related Purpose Measurement IV DV Parametric Tests Independent t-test I Test the difference between 2 independent group means N I/R Paired t-test R Test the difference between 2 related group means N I/R 1-way analysis of variance (ANOVA) I Test the difference the means of 3+ independent groups N I/R Repeated measures ANOVA R Test the difference among the means of 3+ related groups or sets of scores N I/R Pearson correlation I, R Test the existence of a relationship between 2 variables I/R I/R Linear regression -- Predict of DV for given value of IV I/R I/R Nonparametric Mann-Whitney U-test I Test the difference in of scores of 2 independent groups N O Wilcoxon signed-rank test R Test the difference in ranks of scores of 2 related groups N O Kruskal-Wallis test I Test the difference in ranks of scores of 3+ independent groups N O Friedman test R Test the difference in ranks of scores of 3+ related groups N O Chi square test I Test the difference in proportions in 2+ independent groups N N McNemar test R Test the difference in proportions for 2 related groups (2x2) N N Cochran’s Q test R Test the difference in proportions for 3+ related groups N N Fisher’s test I Test the difference in proportions in 2 independent groups when N < 30, any expected cell frequency < 5, or cell with observed frequency of 0 N N Phi coefficient or odds ratio I Examine the magnitude of a relationship between 2 dichotomous variables N N Cramer’s V I Examine the magnitude of a relationship between 2 variables (not restricted to dichotomous) N N Spearman’s rho I, R Test the existence of relationship between 2 variables O O IV, Independent variable; DV, dependent variable; I, independent; R, related; N, nominal; O, ordinal or non-normally distributed interval/ratio; I/R, interval/ratio. Note: On some tests, the measurement level of the IV & DV can be switched. Multivariate/Multivariable & Advanced Statistical Tests
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