When using a DOMAIN statement, if a domain has n levels, the OUTPUT statement in PROC SURVEYLOGISTIC will produce a new data set with (n+1)*nobs observations, where nobs is the number of observations in the input data set. When predicted values are requested, the data set includes predicted probabilities for the overall model (as if there were no DOMAIN statement) and predicted values for each of the n domains. Predicted values are produced for in-domain and out-of-domain observations using the estimates for each particular domain. See SAS KB0058145 for more information about this. This allows you to select any subset of interest from a single data using a DATA step or WHERE statement.