What are the differences between PDAS and RDAS?

PDAS
The Public-use Data Analysis System (PDAS) is an online analysis tool for users to analyze public-use data files (PUFs). This tool allows users to review study variables, run crosstab analyses, perform logistic regressions, and download the results of any analysis to CSV format.

RDAS
The Restricted-use Data Analysis System (RDAS) is an online tool that lets users output custom crosstabs using restricted-use NSDUH files (RUFs) that pass built-in confidentiality restraints. It is similar to the publicly-accessible PDAS tool, except it is populated with restricted data, including certain geographic identifiers not available in the NSDUH PUFs.

RDAS has most of the variables available on the full RUF, including state identifiers. All RDAS estimates use a minimum of two years of pooled data; single-year estimates are not available using RDAS. Only the NSDUH data will be available in the initial release of RDAS.

RDAS is available for all users. Select Analyze > Restricted Data from the SAMHDA toolbar to open RDAS.