Nonparametric Statistical Analysis


 Refers to the use of statistical tests or methods when the data being studied comes from a sample or population of people that does not follow a normal distributed.
 Assumes patient population being studied is not normally distributed (i.e., as seen with outliers)
 Type of data: Nominal or Ordinal.
 Nominal:
 When numbers are assigned to characteristics for the purpose of data classification. Does not have a sense of order or rank.
 Ordinal:
 When numbers are
assigned to data that a sense of rank or order, but the magnitude of difference
between those numbers is not known.
 The usual central measure is a median
 MannWhitney test (assumes 2 independent groups (i.e., not related) being studied)
 KruskalWallis test (assumes > 2 independent groups
being studied/compared)
 Spearman (correlation test)
Definition
Characteristics
Examples of Nonparametic Statistical Tests