ABSTRACT
Background A lack of information about trends in the incidence of regular heroin use hinders eective drug policy and public health action. Yet incidence trends are still unknown almost everywhere in the world. Various estimation methods have been developed to estimate the incidence of heroin use [1-4], however they have requirements, like long-term treatment data or reliable drug mortality statistics, which are rarely available. We have recently reported estimates of incidence and prevalence trends in regular heroin use in Zurich, Switzerland [5]. ese estimates were produced using the Reporting Delay Adjustment (RDA) method and were based on data from a long-term case register that covered all methadone treatments for more than a decade. e RDA method led to prevalence estimates that were in good accord with prevalence estimates generated by other approaches. We have also developed a simpler procedure to estimate the incidence of regular heroin use, called the General Inclusion Function (GIF) method, which only requires methadone treatment data from a single day [6]. On the premise that heroin dependence is usually a chronic condition, we have hypothesized that if governmental regulations do not restrict access the probability of an individual being in substitution treatment depends largely upon time since onset of regular heroin use. e GIF approach led to reasonably good incidence estimates in the canton of Zurich, despite the presence of open drug scenes and irrespective of
whether onset of regular heroin use occurred during an early or a late phase of the ‘heroin epidemic.’
