The use of behavioural self-reports of drug users is widespread among
studies of illicit drug use. Despite widespread use, concerns about th
e accuracy of these reports continue to be raised. The current paper c
ritically reviews the literature on the reliability and validity of se
lf-reported drug use, criminality and HIV risk-taking among injecting
drug users. The literature shows respectable reliability and validity
of self-reported behaviours when compared to biomarkers, criminal reco
rds and collateral interviews. It concludes that the self-reports of d
rug users are sufficiently reliable and valid to provide descriptions
of drug use, drug-related problems and the natural history of drug use
. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.