National Household Survey on Drug Abuse, 1985 (ICPSR 6844)

1. Data were collected by the Temple University Institute for Survey Research, Philadelphia, PA, under contract with the National Institute on Drug Abuse. The data and codebook were prepared for release by Research Triangle Institute, Research Triangle Park, NC, and the codebook was initially distributed by National Opinion Research Center, Chicago, IL, under contracts with the Substance Abuse and Mental Health Services Administration.

2. For selected variables, statistical imputation was done following logical imputation to replace missing responses. These variables are identified in the codebook as "...LOGICALLY IMPUTED" and "...imputed" for the logical procedure or by the designation "IMPUTATION-REVISED" in the variable label when the statistical procedure was also performed. The names of statistically imputed variables begin with the letters "IR". For each imputation-revised variable there is a corresponding imputation indicator variable that indicates whether a case's value on the variable resulted from an interview response or was imputed by the hot-deck technique. Hot-deck imputation is described on pages 16-17 of the codebook.

3. Sample weights were constructed following data collection to account for sample households and persons who were not at home or refused to participate. The household sampling weight is the product of four stagewise sampling weights, each of which is equal to the inverse of the selection probability for that stage. Two post-stratification adjustments were made to compensate for differential response rates across demographic subgroups and residual deviation of selected demographic characteristics of the sample from parameter data (based on the 1980 Census).

4. To protect the confidentiality of respondents, all variables that could be used to identify individuals have been encrypted or collapsed in the public use file. These modifications should not affect analytic uses of the public use file.

5. Revisions involving the editing of recency-of-use variables and removal of ineligible respondents were made to the original 1985 National Household Survey on Drug Abuse (NHSDA) data file to make it more comparable with later NHSDAs. This resulted in several differences between the original and public use files. Although differences in prevalence estimates are generally small, estimates contained in the National Institute on Drug Abuse publication, 1985 NHSDA MAIN FINDINGS, cannot be replicated using the public use file.

6. For some drugs that have multiple names, questions regarding the use of that drug may be asked for each distinct name. For example, the use of methedrine and desoxyn are measured separately in this study even though they are both methamphetamine.

personal interviews and self-enumerated answer sheets (drug use)

• United States Department of Health and Human Services. National Institutes of Health. National Institute on Drug Abuse. National Household Survey on Drug Abuse, 1985. ICPSR06844-v4. Ann Arbor, MI: Inter-university Consortium for Political and Social Research [distributor], 2015-11-23. http://doi.org/10.3886/ICPSR06844.v4

2015-11-23 Covers for the PDF documentation were revised.

2015-02-03 Created a separate Questionnaire PDF that was extracted from the Codebook PDF.

2013-06-19 Updated variable-level ddi files released.

2008-07-25 New files were added. These files included one or more of the following: Stata setup, SAS transport (CPORT), SPSS system, Stata system, SAS supplemental syntax, and Stata supplemental syntax files, and tab-delimited ASCII data file. Also the variable CASEID was added to the dataset. Some other minor edits were made to improve the data and documentation.

1999-06-16 SAS and SPSS data definition statements have been updated to include value labels and missing values sections.

1997-05-16 ICPSR data undergo a confidentiality review and are altered when necessary to limit the risk of disclosure. ICPSR also routinely creates ready-to-go data files along with setups in the major statistical software formats as well as standard codebooks to accompany the data. In addition to these procedures, ICPSR performed the following processing steps for this data collection:

• Performed consistency checks.
• Standardized missing values.
• Created online analysis version with question text.
• Checked for undocumented or out-of-range codes.