SUDAAN is a software product designed and developed by RTI statisticians for analyzing clustered data arising in many applications, including complex sample surveys, randomized experiments, and epidemiological studies. SUDAAN offers procedures for descriptive statistics and for statistical modeling. The modeling procedures include both linear and multinomial-logistic models and a procedure for fitting proportional hazards (Cox) regression models for time-to-event data.

SUDAAN fits marginal or population-averaged models using generalized estimating equations (GEE). Robust variance estimates are computed that fully account for intracluster correlation, unequal weighting, stratification, and without-replacement sampling.

SUDAAN is the only software package to offer all three popular robust variance estimation methods in its descriptive and modeling procedures:

  • Taylor series linearization (GEE for regression models)
  • Jackknife (with or without user-specified replicate weights)
  • Balance repeated replication (BRR)

Together, these procedures and techniques provide a powerful variety of analytic tools not available in other software packages.

SUDAAN statistical experts are available for short- and long-term consulting assignments to help prepare your data for input into SUDAAN. We can also assist with SUDAAN programming, determining the appropriate design options for your particular analysis, and interpreting results from SUDAAN.

For more information or to order online, visit the SUDAAN website.