biostat tests

yipee

independent groups t-test / student’s t-test / parametric test

• dichotomous indep.

  • normal distribution

• continuous dep.

1 group t-test

rarely used; compares sample mean to population mean

paired sample t-test

• paired samples

• continuous dep.

wilcoxon sign-rank

• paired samples

• ordinal dep.

• continuous dep. (if doesn’t meet assumptions for t-test)

mann-whitney U / wilcoxon rank-sum / nonparametric test

• dichotomous indep.

• ordinal dep.

• continuous dep. (if doesn’t meet assumptions for t-test)

x² test

• 2+ dichotomous indep.

• categorical dep.

at least 5 in each group

fisher’s exact test

• 2+ dichotomous indep.

• categorical dep.

used when assumptions for x² not met

analysis of variance / ANOVA

• 3+ dichotomous indep.

  • normal distribution, equal variance

• continuous dep.

kruskal-wallace test

• 3+ dichotomous indep.

  • nonparametric distribution

• ordinal dep.

• continuous dep. (if small groups)

mcnemar test

one sample

• categorical dep.