title: Correspondence analysis in medical research.
abstract: Various applications of correspondence analysis to biomedical data are presented. The basic concepts of profile, mass and chi-squared distance are introduced in an initial simple example using data on the relationship between headache types and age. The main result of the correspondence analysis is a geometric map of this relationship showing how the relative frequencies of headache types change with age. A second example maps the association between personality types and various medical diagnostic groups, while a third example deals with categorical rating scales such as an efficacy scale for a medication or a scale of pain. A final example illustrates the more complex situation when several categorical variables are involved using test data on a collection of bacterial isolates, with the object of comparing bacterial types and understanding the inter-relationships of the different tests.
authors.affiliation: Department of Statistics, University of South Africa, Pretoria.
authors.forename: M
authors.initials: M
authors.lastname: Greenacre
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D017347:Brucella melitensis / Q000145:classification; D002648:Child; D003627:Data Interpretation, Statistical; D006261:Headache / Q000145:classification; D006801:Humans; D008432:Mathematical Computing; D008875:Middle Aged; D010551:Personality / Q000145:classification; D012984:Software; D016019:Survival Analysis