What is SUDAAN?

SUDAAN (Survey Data Analysis) is a statistical software package designed for the analysis of complex sample survey data. It accounts for stratification, clustering, and unequal probabilities of selection, which are common features of survey designs. By properly accounting for these design effects, SUDAAN provides accurate variance estimates and confidence intervals for survey-based estimates, avoiding the underestimation of standard errors that can occur when using standard statistical packages that assume simple random sampling. It's commonly used in public health, epidemiology, and social sciences for analyzing data from surveys like NHANES, BRFSS, and other large-scale national surveys.