Estimating drug consumption in opioid users: reliability and validity of a 'recent use' episodes method.

The efficient and accurate measurement of recent drug use is an essential component of treatment and research among opioid users. Urinalysis results alone will not give sufficient information to either the clinician or researcher, due to limitations in detection and an inability to distinguish extent of use. The present paper describes a 'recent use episodes method', adapted from the measurement of alcohol consumption, for obtaining self-reported drug use in eleven different drug categories. Reliability and validity data indicate that the method provides a quick means by which accurate information may be obtained on the overall recent drug use of opioid users.