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).

How do I correctly calculate N-SSATS client counts and admissions using SDA?

The N-SSATS is a database of facilities, not clients or admissions. Thus, calculating client counts / admissions using one of the client counts / admissions variables might produce unexpected results. This note describes how to correctly calculate client counts and admissions for N-SSATS data.

The client counts and admissions variables are listed in the following sections of the codebook:

• Section B: Reporting Client Counts
• Hospital Inpatient Client Counts
• Residential (Non-Hospital) Client Counts
• Outpatient Client Counts
• Totals and Percentages
• (Excluding the variables that give percentages)
• Section 7: Added variables

To correctly calculate client counts or admissions, do the following:

1. Access N-SSATS within SDA.
2. Go to the "Analysis" menu (top left) and select "Comparison of means".
3. For the "Dependent" variable, specify one of the client counts or admissions variables. For example, specify T_METH for the total number of methadone clients on the reference date.
4. Specify an appropriate "Row" variable, such as STFIPS for the state.
5. Specify the "Column", "Control", and "Selection Filter(s)" variables as needed. For example, under "Selection Filter(s)", you might state "YEAR(2010), OTP(1)" to restrict analysis to the year 2010 and to facilities that operated a certified Opioid Treatment Program.
6. Set the "Main statistic to display" to "Totals (numerator of means)". This is a key step.
7. Under "Table Options" uncheck all the checkboxes.
8. Make any other adjustments to the display options that are necessary. For example, if you don't want a chart, change "Type of Chart" to "(No Chart)".
9. Click "Run the Table". The output table from this example gives the total number of methadone clients on the reference date by state in 2010 in facilities that operated a certified Opioid Treatment Program.