The pitfalls of prevalence estimation: the case of regular and dependent methamphetamine use in Australia

Abstract

Objectives: The prevalence of regular and dependent methamphetamine use in Australia in 2013/14 was recently estimated indirectly using multipliers at 268,000 regular (defined as >monthly use in the past 6 months) and 160,000 dependent (defined as >3 on the Severity of Dependence Scale) methamphetamine consumers, respectively. We replicated this approach using more contemporary multipliers and alternate data sources to explore identified limitations with this approach. Design: Two multipliers were derived from surveys of methamphetamine consumption in Sydney (NSW) in 2003/04 (the original multiplier) and Melbourne (VIC) in 2010 (a more contemporary multiplier), and applied to the time series..