The validity of self-reported drug use in survey research: an overview and critique of research methods.

Since illicit drug use is by definition illegal, the tasks of measuring incidence and prevalence and charting the course of the epidemic have fallen to survey researchers over the past 30 years. Although survey methods have obvious advantages over indirect measures such as arrests, seizures, and treatment admissions, they are frequently criticized because the rely on valid self-reporting of sensitive and highly stigmatized behavior. Validation studies conducted before the mid-1980s involving known samples of drug users or urinalysis techniques suggested that drug use was fairly accurately reported in self-report surveys. However, more recent validation studies conducted with criminal justice and former treatment clients using improved urinalysis techniques and hair analyses demonstrate that self-report methods miss a lot of recent drug use. A review of the research literature suggests that neither self-reports nor bioassays are wholly accurate, and both have inherent problems. However, because self-report measures are necessary to understand the complexity of causal and correlational attributes of drug abuse, it is necessary to determine what can be done to improve valid self-reporting. This chapter examines the research literature on validation studies to provide an overview of what is known about the accuracy of self-reported drug use.