The methodology of published population-based burden-of-headache studies has been variable, hindering comparisons, and not always adequate, hindering interpretation. It should be optimised and standardised, especially for application in developing countries with relatively inaccessible populations.

Our project is conceived in three parts with three outputs:

1. Review of the literature, and a discussion of the headache-specific epidemiological issues;
2. Formulation of practical methodological guidelines, by convening an expert consensus group (who met at NTNU) and undertaking wide consultation;
3. Development of a survey instrument (questionnaire) based on expert opinion and worldwide empirical field-testing.

Collaborators:

• M Al Jumah, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
• GL Birbeck, University of Rochester, Rochester, NY, USA, University of Zambia, Lusaka, and Chikankata Health Services, Mazabuka, Zambia
• S Chatterji, World Health Organization, Geneva, Switzerland
• T Dua, World Health Organization, Geneva, Switzerland
• G Gururaj, National Institute for Mental Health and Neurosciences (NIMHANS), Bangalore, India
• R Jensen, Danish Headache Center, Glostrup Hospital, Glostrup, Denmark
• Z Katsarava, University of Duisburg-Essen, Essen, Germany
• RB Lipton, Albert Einstein College of Medicine, Bronx, NY, USA
• LP de Queiroz, Universidade Federal de Santa Catarina, Florianopólis, SC, Brazil
• AI Scher, Uniformed Services University, Bethesda, MD, USA
• R Tekle-Haimanot, Addis Ababa University, Addis Ababa, Ethiopia
• S-J Wang, National Yang‐Ming University School of Medicine and Taipei Veterans General Hospital, Taipei, Taiwan