The European drug index: Measuring and comparing national substance use across the European Union to aid policy and planning

Introduction Despite individual European-wide indicators, there is a dearth of tools that holistically assess substance use and related problems. To address this critical research gap, this paper presents a method used to construct aggregated indices that measure and compare the prevalence of substance use, treatment coverage, syringe distribution, and overdoses per capita across the EU as a whole and by age, gender, and substance class. Methods An indicator-based approach was used to create aggregated indices from 151 indicators for 27 EU member states. Indicators were classified, and aggregate indices were created, for distinct cohorts (e.g., general population, male, female, younger, and older) and substances (e.g., alcohol, cannabis, tobacco, opioids). Results The average EU performance for most indicators was considered either poor or moderate. General patterns emerged where Eastern Europe performed better than Western Europe, and more nations performed strongly on indices related to legal rather than illegal substances. Nations that were among the highest performers in the Male Index were among the highest performers in the Female Index. Nations that performed well in the Younger Index did not necessarily perform well in the Older Index, except Portugal, which achieved high rankings in both. Discussion The results highlight the need for a more thorough analysis of substance use indicators and a nuanced and evidence-based approach to substance use policymaking. As an initial exploration, the index presents a potentially uniquely valuable tool that can be further developed to directly inform policy and intervention development.