title: [Analysis of ordinal repeated measures data using generalized estimating equation].
abstract: OBJECTIVE
  To explore the application of the generalized estimating equation in the ordinal repeated measures data and hence provide methodology reference for the analysis of repeated measures data in the clinical trials.
  
  
  METHODS
  An example was illustrated by modeling generalized estimating equation using the GENMOD command in comparison with the independent logistic regression.
  
  
  RESULTS
  All parameters and their standard error were estimated, so every factor could be dealt with intuitive estimation of parameter. The standard errors of coefficients in generalized estimating equation are generally greater than that in independent logistic regression.
  
  
  CONCLUSIONS
  Generalized estimating equation can solve the correlation between the dependent data by using working correlation matrix, and it can control strata correlation, repeated measures factor and other confounding factors effectively, so generalized estimating equation provides an effective method for the ordinal repeated measures data.
authors.affiliation: Department of Health Statistics, West China School of Public Health, Sichuan University, Chengdu 610041, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Liu
authors.forename: Ju-ying
authors.initials: JY
authors.lastname: Zhang
mesh_terms: D002986:Clinical Trials as Topic / Q000379:methods; D003627:Data Interpretation, Statistical; D016014:Linear Models; D016015:Logistic Models