National Household Survey on Drug Abuse/Age of First Use

Abstract

The Age of First Use (AFU) scale is a key component derived from the larger National Household Survey on Drug Abuse (NHSDA), sponsored by the Substance Abuse and Mental Health Services Administration (SAMHSA). Developed in 1999, this instrument is designed to quantitatively assess the age at which respondents first initiated the use of various legal and illicit substances, providing critical epidemiological data for public health research and policy formulation.

This module focuses on capturing precise retrospective self-report data concerning the initial exposure to seven major categories of substances, ranging from tobacco and alcohol to hard drugs like heroin and cocaine. The resulting data is fundamental to understanding the chronological progression of substance involvement and risk factors associated with early initiation.

Keywords

Drug Abuse, Age of First Use, Substance Use Initiation, NHSDA, SAMHSA, Epidemiology, Alcohol Use, Tobacco Use, Illicit Drugs.

Authors

Substance Abuse and Mental Health Services Administration (SAMHSA)/Office of Applied Studies (OAS), and Research Triangle Institute (RTI).

Purpose

The primary purpose of the Age of First Use (AFU) scale is to establish precise longitudinal data regarding substance use patterns across the U.S. population. This information is crucial for understanding the chronological progression of substance involvement, which is a key indicator of future substance abuse risk.

By collecting the specific age of initial exposure to substances, researchers can identify critical periods of vulnerability, evaluate the effectiveness of prevention programs, and model the trajectory from initiation to potential substance use disorders, thereby informing national public health policy and resource allocation.

Construct

The scale measures the behavioral psychological construct of Substance Use Initiation Timing. This construct is operationalized as the chronological age (in years) at which an individual first tried or experimented with a specific category of substance, including tobacco, alcohol, marijuana, and various hard drugs.

The timing of first use is considered a fundamental predictor in addiction research. Early initiation is consistently correlated with an increased likelihood of developing substance dependence, greater severity of future drug involvement, and poorer long-term health outcomes compared to initiation later in life.

Validity

As a core component of a major government survey, the validity of the AFU items is intrinsically linked to the overall methodology of the NHSDA. The scale utilizes self-report data, making recall bias a potential factor, especially for events that occurred many years prior.

To enhance validity, the NHSDA employs rigorous survey administration protocols, including the use of Computer-Assisted Self-Interviewing (CASI) methods. These methods help increase respondent privacy and reduce the likelihood of social desirability bias when reporting sensitive behaviors like illicit drug use, improving the accuracy of the reported age of first use.

Reliability

Given that the AFU scale consists of independent, single-item questions measuring specific events (age of initiation), traditional internal consistency measures (e.g., Cronbach’s alpha) are not applicable. Reliability is generally assessed through test-retest procedures conducted during pilot phases of the larger NHSDA framework.

Research suggests that retrospective self-reports of the age of first use for highly salient events, such as alcohol or cigarette initiation, demonstrate acceptable temporal stability. This consistency ensures that the data collected is reliable for generating accurate population-level epidemiological statistics and tracking trends over time.

Factor Analysis

The Age of First Use scale is composed of independent items designed to capture specific demographic data points (the age of a single event). Therefore, factor analysis is not typically performed or relevant for this instrument, as the items do not measure a common latent psychological factor but rather distinct instances of initiation across different substance categories.

The data collected from the AFU scale is generally analyzed using descriptive statistics or used as an independent predictor variable in complex regression models, rather than being aggregated into a composite score.

Instrument

Test Type: Epidemiological Survey Module; Retrospective Self-Report

Format: Structured questionnaire requiring numerical input (age in years) or a categorical selection (never used).

Language Available: English (standard for the National Household Survey on Drug Abuse).

Population Group: General household population.

Age Group: Typically utilized for individuals aged 12 and older.

Population Details: Non-institutionalized civilian population of the United States.

Test Methodology: Self-administered questionnaire, often utilizing Computer-Assisted Self-Interviewing (CASI) to ensure privacy and accurate reporting of sensitive information regarding the Age of First Use.

Keywords

Substance Dependence, Public Health, Initiation Timing, CASI, Research Triangle Institute, SAMHSA, Drug Policy.

Authors

Author ORCID Identifier: N/A (Organizational authorship)

Affiliation Email addresses: N/A (Public Domain/Organizational)

Correspondence Address: Research Triangle Institute, P.O. Box 12194, Research Triangle Park‚ NC 27709-2194, (919) 485-2666.

Permissions & Fee and Test Year

The National Household Survey on Drug Abuse (NHSDA) instrument, including the Age of First Use scale, is categorized as Public Domain content, having been developed and published by the U.S. government agency SAMHSA/OAS. No usage fees are required for access or utilization.

The scale was formally cited in publications beginning in 1999, reflecting the data collection period of the 1998 NHSDA.

Reference’s

Substance Abuse and Mental Health Services Administration (1999). Summary of Findings from the 1998 National Household Survey on Drug Abuse. Office of Applied Studies‚ DHHS Publication No. (SMA) 99-3328. Rockville‚ MD.

The instrument in its original context can be found on pages 27-28 of Core Measures Initiative Phase I Recommendations‚ Center for Substance Abuse Prevention. The original PDF can be downloaded here: http://vvv.dmhas.state.ct.us/sig/pdf/uconn/core_measures.pdf

Items of the National Household Survey on Drug Abuse/Age of First Use

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.