Using Monte Carlo simulation to assess uncertainty and variability of methamphetamine use and prevalence from wastewater analysis

Background In recent years, methamphetamine (METH) has increased dramatically in China. However, little is known regarding the prevalence of METH use among the general population in China. Methods We provided a method to estimate the consumption and prevalence of METH in a city based on wastewater analysis. Monte Carlo simulations were employed to assess the uncertainty and variability of the consumption and prevalence rate in Beijing. Results METH consumption in Beijing based on Monte Carlo simulation varied between 1.3 and 5.2kg per day with a median of 2.6kg per day. In 2013, the 12-month prevalence of METH use was 0.58% (95% confidential interval 0.08–3.16) among the general population aged 15–64 years. A population-weight consumption map displayed the geographical differences in Beijing. Conclusions The proposed method dramatically improved the accuracy and reliability and can be used as a useful complementary tool to official methodologies for drug use monitoring. This report describes the first comprehensive study concerning the prevalence of METH among the general population in mainland China.