Introduction: The parent study was a survey in 28 headache centers (6 countries) which identified five potential root causes for long waiting lists that limit patient access to specialist care. Here we performed an extension of the parent study to increase the panel of centers contacted, the representativeness of the analysis, and the statistical validity of the results, and to explore the role of dedicated headache clinics, triage, and specialized nurses. Methods: We conducted a 19-question survey using a sample of 239 headache centers (16 countries). The five-area framework identified Digital Features To view digital features for this article go to