This is the third issue of the EMCDDA’s statistical bulletin. It will continue to be presented only in English and available only as an Internet publication. The bulletin is a companion publication to the EMCDDA annual report and provides a complementary information source. It supplies the user with the data tables collated by the EMCDDA from the information submitted by the national focal points Reitox network. These tables constitute the epidemiological basis on which the annual report is written and are frequently referenced by it. In addition to the tables of data and the accompanying graphics, the bulletin gives detailed technical commentaries, notes and descriptions.

This year reporting covers in most cases, where data are available, the enlarged EU, Norway and the candidate countries. The expanded bulletin again includes information on methadone substitution and needle and syringe programmes and exchange facilities in the EU and hopes to continue this monitoring. Each topic this year has an added gloss, summarising the main points as an aid to interpreting the relevant tables. The graphical presentation section as it did last year gives a link to a set of individual country data profile pages for selected prevalence indicator information.

As in the revised edition last year, this year the division of the bulletin by topic includes the methodological notes and the overview summaries for each indicator area, arranged as a set of chapters. But, for readers wishing to go straight to the data tables, there is the index of tables and graphics.

The commentary section in this 2006 edition of the bulletin focuses on two issues: the downward trend in the price of drugs and the estimates of the availability of syringes to injecting drug users. In future the bulletin is planned to comment on recent trends in more technical detail than can be presented in the annual report.

The tables are presented for screen browsing (see table of contents) and also in an accessible and editable form for downloading and printing individually. For information on downloading tables and text the user should consult the help section of the bulletin. Some of the information recorded at the EMCDDA is held in tables that are very large. Typically this information consists of lists of research studies in the key indicator fields. These have been included as supplementary tables that are available online on the EMCDDA website, usually in spreadsheet format, for downloading.

The methods and definitions sections (see table of contents) collect together summary information on the EMCDDA guidelines and protocols for each of the key indicators and the associated developing areas of core data. These sections give descriptions and definitions used in collecting the data for the main tables, and comments on their rationale and implications. They contain links to the more detailed descriptions of the guidelines and protocols found elsewhere on the EMCDDA website. There are no major revisions this year.

Data coverage and comparability

Sampling and coverage in the collection of the data are important issues in the interpretation of national data. For example, treatment report data are derived from systems that may only have partial coverage of the national treatment capacity or only cover particular sectors of the drug treatments available in Member States. For treatment demand data and first treatment demand data, double-counting of the same individual in registers is also an issue, although most systems attempt to control for this.

Overall data availability for the new Member States of the EU is more limited, with some notable exceptions. The EMCDDA has been working for several years (supported by the PHARE programme) to establish drug information systems. This is reflected in the fact that some of the new Member States have an impressive visibility in the data tables for the more recent years of reporting (2000 onwards).

For many of the tables, the reporting units used or methodological considerations mean that it is difficult to compare prevalence levels and other drug indicator information directly across different countries. The considerable heterogeneity of countries in population size and the differences in the nature of national drug situations are reflected in considerable heterogeneity in the scale of the national absolute figures. The reader should therefore be very cautious in drawing conclusions from overall European trends about the trend for an individual country, or vice versa, because European trends often are heavily influenced by the data from a few large countries. Similarly, the failure of a large country to report in for a particular year can markedly influence the overall European trend for that year and the overall pattern of the trend could be distorted.

From the data in the bulletin the EMCDDA seeks to present a unified picture for the EU Member States and also to highlight important differences. Due to the inherent difficulties in collecting data on illicit drug use, especially with respect to sampling issues, the reader is advised to use caution in drawing conclusions based on small differences. Assessing the significance of differences between countries and changes over time in a more technical fashion is usually impossible with the information currently reported to the EMCDDA. In analysing the data from these tables it is therefore always important to consider the more general picture, to note the overall influence of each particular country and to bear in mind the differences in national trends from overall European trends. Specific caveats on interpretation and comparison are important when looking at these data sets, and the footnotes to each table highlight where there are obvious discrepancies in method and non-comparability of information across different countries. These issues are described more generally in the Commentary section of the 2004 bulletin.

General population surveys are one data source that directly aims to reflect a common phenomenon in each country. Although the detail of the survey methods may be different in each country – as they should be to take account of varying national and local patterns of use and social structures – the estimated general prevalence levels of drug use are a basic marker for all countries. The principal caveat in using such data is to remember that for the most part these are self-reported use levels, not usually backed by pharmacological testing. The following section uses general population survey data from the EU countries in comparison with survey data from the USA.

The expansion of the EU unavoidably means that many tables of data are incomplete, some with a large number of missing items of information, and they necessarily show only a partial picture of the European drug situation for both older and newer countries. Progress in this respect has been made since 2004 and the table structures in the 2006 bulletin have changed and may change again in the future as the data continues to develop into towards providing a fuller European picture.