The third edition of the International Classification of Headache Disorders (ICHD-3) is now available in its final form in German translation. It can be accessed via the following link on the ICHD-3 website.

https://www.ichd-3.org/ichd-3-translations/

can be viewed.

Special thanks are due to Prof. Dr. Dr. Stefan Evers, Secretary General of the International Headache Society, who organized the translation work so successfully and effectively.

Professor Jes Olesen, Chair of the Headache Classification Committee of the International Headache Society, writes in his foreword to ICHD-3: “ICHD-3 is published as the first issue of the journal Cephalalgia 2018, exactly 30 years after the first edition of the International Classification of Headache Disorders , ICHD-1, as we now call it. This first edition was primarily based on expert opinion, but nevertheless proved largely valid. ICHD-2, published in 2004, incorporated a number of changes, some prompted by new findings and others based on expert opinions that have since been revised. New scientific findings played a comparatively larger role in the changes made to ICHD-3 beta, and all further innovations included in ICHD-3 are based on such findings. Headache classification is therefore fully based on research today and will continue to be so in the future.”

With the publication of the ICHD-3, a long journey that began in 2010 comes to an end, but the current committee still has a considerable amount of work ahead of it in the coming years. The ICHD-3 beta has been translated into many languages, and these translations need to be updated before the ICHD-3 can be published in the respective languages. It is hoped that many more translations will be released so that the ICHD-3 will be accessible in all common and even many less common languages. An electronic version of the ICHD-3, already prepared under the direction of Professor Hartmut Göbel, will be updated to the ICHD-3 standard. Furthermore, the publication of a casebook is planned in collaboration between Professor Morris Levin and Professor Jes Olesen. Finally, Professor Timothy Steiner and Professor Jes Olesen will establish a link between the ICHD-3 and the WHO's ICD-11 as soon as the ICD-11 codes are available.

So what does the future of headache classification look like? A classification must, in principle, be conservative. As soon as major changes are made to a classification, all previous studies that relied on these now-modified parts of the classification must be revisited. Drug trials, for example, conducted according to the previous diagnostic criteria must be repeated if there are significant changes to the diagnostic criteria, because the patients falling under the new diagnosis will differ from those falling under the previous diagnosis. My hope is that the active field studies and scientific analysis undertaken for ICHD-3 will continue, ensuring that future changes will be fully evidence-based. Traditionally, it will take 10-15 years until ICHD-4, but numerous field studies will be conducted in the meantime. Modified diagnostic criteria for ICHD-II for chronic migraine were published in the journal Cephalalgia . The classification committee approved these changes and requested their immediate implementation, even though they had not yet been incorporated into the International Classification of Headache Disorders ( ICHD-3 beta), until years later when ICHD-3 beta was published. A future headache classification committee should similarly be able to approve and support the establishment of new or revised diagnostic criteria prior to the publication of ICHD-4, provided these criteria are supported by sound field studies published Cephalalgia

With the headache classification in the ICHD-1, headaches transformed from among the worst-classified neurological disorders to among the best-classified. We have maintained this momentum for 30 years, and the superiority of our classification was recently demonstrated during the committee's work in Geneva on the neurological section of the ICD-11. No other specialty within neurology has such a systematic classification with explicit diagnostic criteria for each disease entity. I sincerely hope that this tradition will continue in the future and that the headache classification will thus become a pioneer for the classification of neurological disorders in general