• When numbers are assigned to characteristics for the purpose of data classification arbitrarily and without any regard to order.

• The numbers selected or assigned to a variable are arbitrary.
• Data endpoints are assigned these arbitrary numbers without any regard to order or rank.

• Gender:
• Females are assigned the number 1
• Males are assigned the number 2
• Mortality:
• Being alive at the end of a study is assigned the number 1
• Being dead at the end of a study is assigned the number 2

• Nonparametric Statistical Analysis
• Parametric Statistical Analysis
• Ordinal Data
• Continuous Data
  

1. Gaddis ML et al. Introduction to biostatistics: part 1, basic concepts. Ann Emerg Med 1990;19:86-89.

Editors:

• Anthony J. Busti, MD, PharmD, FNLA, FAHA
  

Last Reviewed: July 2015