1979-08 -- 1980-01
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.
The codebook, which includes the data collection instruments, is provided as a Portable Document Format (PDF) file.
New editing, revised handling of missing data, and different sampling weights were applied to the original 1979 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, published findings of the 1979 NHSDA cannot be replicated using the public use file.
Data were collected by Response Analysis Corporation, Princeton, NJ, under contract with 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.
To protect the confidentiality of respondents, all variables that could be used to identify individuals have been encrypted, collapsed, or deleted. These modifications should not affect analytic uses of the data.
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, which is described in the codebook.
The "basic sampling weights" are equal to the inverse of the probabilities of selection of sample respondents. To obtain "final NHSDA weights," the basic weights were adjusted to take into account dwelling unit-level and individual-level nonresponse and further adjusted to ensure consistency with population projections from the United States Bureau of the Census.