Free tool

Which statistical test should I use?

Answer a few questions about your hypothesis and your data, and get the test that fits, with a guide on how to run and report it.

All tests at a glance

Test	When to use it
Independent-samples t-test Independent, Paired or One-Sample t-Test: Which One Fits Your Paper	Comparing the mean of a continuous variable between two separate groups, e.g. men and women.
Paired-samples t-test Independent, Paired or One-Sample t-Test: Which One Fits Your Paper	Comparing the mean of the same participants at two measurements, e.g. before and after an intervention.
One-way ANOVA One-Way ANOVA and Post-Hoc Tests: A Guide for Your Seminar Paper	Comparing means across three or more separate groups, followed by post hoc tests.
Repeated-measures ANOVA How to choose a statistical test: a quick guide for your paper or thesis	The same participants at three or more measurements, e.g. three time points.
Two-way ANOVA Two-Way ANOVA and Interactions: How to Read, Interpret and Report Them	The effect of two independent variables, and their interaction, on a continuous variable.
Mann-Whitney U test When to use the Mann–Whitney test, and how to report it	The non-parametric alternative to the independent t-test: two groups, an ordinal variable or a non-normal distribution.
Wilcoxon signed-rank test Non-Parametric Tests: Wilcoxon, Kruskal-Wallis, Friedman and Spearman - When and How	The non-parametric alternative to the paired t-test: the same participants at two measurements.
Kruskal-Wallis test Non-Parametric Tests: Wilcoxon, Kruskal-Wallis, Friedman and Spearman - When and How	The non-parametric alternative to one-way ANOVA: three or more separate groups.
Friedman test Non-Parametric Tests: Wilcoxon, Kruskal-Wallis, Friedman and Spearman - When and How	The non-parametric alternative to repeated-measures ANOVA.
Chi-square test of independence The Chi-Square Test (χ²): When to Use It, How to Run It in SPSS and How to Report It	A relationship between two categorical variables, e.g. gender and choice of track.
McNemar test The Chi-Square Test (χ²): When to Use It, How to Run It in SPSS and How to Report It	A yes/no variable measured twice in the same participants, before and after.
Pearson correlation Correlation or Regression? The Difference, When to Use Each and How to Report It	A linear relationship between two continuous variables.
Spearman correlation Correlation or Regression? The Difference, When to Use Each and How to Report It	A relationship between ordinal variables, or when the distribution is far from normal or there are outliers.
Mediation or moderation model (PROCESS) Mediation and Moderation with PROCESS in SPSS: A Guide for Your Thesis	Mediation: a variable that explains how the relationship works. Moderation: a variable that changes its strength or direction.
Multiple linear regression Correlation or Regression? The Difference, When to Use Each and How to Report It	Predicting a continuous variable from several predictors, including control variables.
Logistic regression Logistic regression in SPSS: how to read the output	Predicting a yes/no outcome from several predictors, with odds ratios (OR).
Structural equation modeling (SEM) What Is SEM? Structural Equation Modeling, Path Analysis and Latent Variables - A Thesis Guide	A full model of latent variables and the relationships between them, including confirmatory factor analysis.
Cronbach's alpha Low Cronbach's alpha: what to do	Checking the internal consistency of a scale before computing a score from it.