What is the Restricted-use Data Analysis System (R-DAS)?

The R-DAS is an online analysis system that allows researchers to produce frequencies and cross-tabulations using restricted-use data files. The R-DAS provides output in the form of tables and frequencies for viewing and exporting. Advanced statistical methods are not available in the R-DAS at this time.

The R-DAS does not permit listing of individual cases and does not provide unweighted frequencies in the R-DAS codebook, nor are users able to generate unweighted frequencies (no unweighted sample sizes are provided). These limitations have been put in place to reduce the potential for disclosing confidential information.

The R-DAS provides standard errors that take into account the complex survey design. All weighted totals and point estimates are rounded to the nearest thousand and all percents and associated statistics are rounded to one decimal point. If any cell in a table contains too few unweighted cases, then the entire table is suppressed.

The R-DAS does not currently allow for the creation of composite variables (i.e., the creation of new variables using other variables), but that capability is under development. The R-DAS does allow for temporary recoding of existing continuous and categorical variables. See the SDA 3.5 help documentation for assistance with how to Temporarily Recode a Variable.

Watch the "Broadening Access to Substance Abuse and Mental Health Data with the R-DAS" webinar to learn about the National Survey on Drug Use and Health (NSDUH) data available through the R-DAS. For more information on analyzing data with the R-DAS, consult the FAQ section on Help with the Restricted-use Data Analysis System (R-DAS).