DOI: 10.3886/icpsr03239.v5
title: National Household Survey on Drug Abuse, 1999
title: Version 5

description: The National Household Survey on Drug Abuse (NHSDA) series
measures the prevalence and correlates of drug use in the United
States. The surveys are designed to provide quarterly, as well as
annual, estimates. Information is provided on the use of illicit
drugs, alcohol, and tobacco among members of United States households
aged 12 and older. Questions include age at first use as well as
lifetime, annual, and past-month usage for the following drug classes:
marijuana, cocaine (and crack), hallucinogens, heroin, inhalants,
alcohol, tobacco, and nonmedical use of prescription drugs, including
pain relievers, tranquilizers, stimulants, and sedatives. The survey
covers substance abuse treatment history and perceived need for
treatment, and includes questions from the Diagnostic and Statistical
Manual (DSM) of Mental Disorders that allow diagnostic criteria to be
applied. Respondents are also asked about personal and family income
sources and amounts, health care access and coverage, illegal
activities and arrest record, problems resulting from the use of
drugs, and needle-sharing. Questions introduced in previous NHSDA
administrations were retained in the 1999 survey, including questions
asked only of respondents aged 12 to 17. These "youth experiences"
items covered a variety of topics, such as neighborhood environment,
illegal activities, gang involvement, drug use by friends, social
support, extracurricular activities, exposure to substance abuse
prevention and education programs, and perceived adult attitudes
toward drug use and activities such as school work. Also retained were
questions on mental health and access to care, perceived risk of using
drugs, perceived availability of drugs, driving behavior and personal
behavior, and cigar smoking. Questions on the tobacco brand used most
often were introduced with the 1999 survey. Demographic data include
gender, race, age, ethnicity, marital status, educational level, job
status, veteran status, and current household composition.
description: Due to unequal selection probabilities at multiple stages of sample selection and the coverage bias, the 1999 NHSDA sample is not
self-weighting. Analysts are advised to use the sample weight when
attempting to use the NHSDA data to draw inferences about the target
population or any subdomain of the target population. All estimates
published in SAMHSA reports (such as the Summary of Findings from the
1999 NHSDA) are weighted. The appropriate and final sample weight is
called ANALWT_C on this data file. This sample weight represents the
total number of target population persons each record on the file
represents. Note that the sum of ANALWT_C, over all records on the
data file, represents an estimate of the total number of people in the
target population.
description: Response Rates: The study yielded a weighted screening response rate
of 90 percent and a weighted interview response rate for the CAI of 69
percent.
description: A multistage area probability sample for each of the 50
states and the District of Columbia was used. A coordinated five-year sample
design was developed for 1999 through 2003. Although there is no
overlap with the 1998 sample, the design facilitated an overlap in
first-stage units (area segments) between each two successive years in
the five-year design. This design was intended to increase the
precision of estimates in year-to-year trend analyses because of the
expected positive correlation resulting from the overlapping
sample. To obtain the required precision at the state level and to
improve the precision of cigarette brand data for youths at the
national level, youths and young adults were oversampled. The result
was that each state's sample was approximately equally distributed
among three major age groups: 12 to 17 years, 18 to 25 years, and 26
years or older. The achieved sample for the 1999 computer-assisted
interview (CAI) sample was 66,706 persons. The public use file has
53,560 records due to the subsampling step used in the disclosure
protection procedures. Minimum item response requirements were defined
for cases to be retained for weighting and further analysis (i.e.,
"usable" cases). These requirements, as well as full sampling
methodology, are detailed in the codebook.
description: Datasets: 
DS1: National Household Survey on Drug Abuse, 1999
description: The civilian, noninstitutionalized population of the
United States aged 12 and older, including residents of
noninstitutional group quarters such as college dormitories, group
homes, shelters, rooming houses, and civilians dwelling on military
installations.
description: audio computer-assisted self interview (ACASI); computer-assisted personal interview (CAPI)Data were collected and prepared for release by
Research Triangle Institute, Research Triangle Park, NC.The National Household Survey on Drug Abuse survey administration and sample design changed with the implementation of the 1999 survey. Starting in 1999, the survey sample has employed a 50-State design with an independent, multistage area probability sample for each of the 50 States and the District of Columbia. Therefore, estimates produced from the 1999, 2000, and 2001 surveys are not comparable to those produced from the 1998 and earlier surveys.For selected variables, statistical imputation was performed following
logical inference to replace missing responses. These variables are
identified in the codebook as "...LOGICALLY ASSIGNED" 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. Missing
values for some demographic variables were imputed by the unweighted
hot-deck technique used in previous NHSDAs. Beginning in 1999,
imputation of missing values for many other variables was accomplished
using predictive mean neighborhoods (PMN), a new procedure developed
specifically for the NHSDA. Both the hot-deck and PMN imputation
procedures are described in the codebook.To protect the privacy
of respondents, all variables that could be used to identify
individuals have been encrypted or collapsed in the public use
file. To further ensure respondent confidentiality, the data producer
used data substitution and deletion of state identifiers and a
subsample of records in the creation of the public use file.Previously published estimates may not be exactly reproducible from
the variables in the public use file due to the disclosure protection
procedures that were implemented.The data definition and
dictionary files for Stata are designed to be compatible with StataSE,
Version 8. This is a large data file requiring that approximately 250
megabytes of Random Access Memory be allocated to Stata. Operations
within Stata, including conversion of the ASCII data to Stata format,
are likely to be slow. Analysts may wish to download subsets of data
from the SAMHDA Data Analysis System (DAS) for use with Stata.