Non parametric tests

Small sample studies constitute a challenge for the internal and external validity of scientific studies. Yet, small sample research is critically important as the research questions posed in small samples often represent serious health concerns in vulnerable and underrepresented populations. Small sample studies usually do not follow the statistical assumptions to conduct parametric statistical tests. An alternative appropriate analysis for this problem is the non-parametric tests.

Workshop items:

• The problem of small sample studies

• Why non-parametric tests are the solution for small sample studies?

• The idea behind non-parametric tests

• Quantitative variables:

  • 2 independent groups

  • > 2 independent groups

  • 2 related groups (or 2 times measurements)

  • > 2 related groups (or > 2 times measurements)

• Qualitative variables:

  • Comparison between independent groups

  • Comparison between related groups

  • Association between 2 quantitative variables

• Application on SPSS