GEECORR: A SAS macro for regression models of correlated binary responses and within-cluster correlation using generalized estimating equations

Comput Methods Programs Biomed. 2021 Sep:208:106276. doi: 10.1016/j.cmpb.2021.106276. Epub 2021 Jul 14.

Abstract

Background and objectives: Generalized estimating equations (GEE) provide population-averaged model inference for longitudinal and clustered outcomes via a generalized linear model for the effect of explanatory variables on the marginal mean, while intra-cluster correlations are ordinarily treated as nuisance parameters. Software to richly parameterize and conduct inference for complex correlation structures in the marginal modeling framework is scarce.

Methods: A SAS macro, GEECORR, has been developed for the analysis of clustered binary data based on GEE to include additional estimating equations for modeling pairwise correlation between binary variates as a function of covariates.

Results: We illustrate the macro in a surveillance study with repeated measures, a longitudinal study, and a study with biological clustering.

Conclusions: This article provides an overview of the GEE method consisting of a pair of estimating equations, describes the features and capabilities of the GEECORR macro including regression diagnostics and finite-sample bias-corrected covariance estimators, and demonstrates the macro usage for three studies.

Keywords: Clustered binary data; Deletion diagnostics; Intraclass correlation; Longitudinal data; Repeated measures.

MeSH terms

  • Bias
  • Cluster Analysis
  • Computer Simulation
  • Humans
  • Linear Models
  • Longitudinal Studies
  • Models, Statistical*