EBM Consult

Nominal Data

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

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

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

    Editors:

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

    Last Reviewed: July 2015