Development and validation of the EUROLIGHT questionnaire to evaluate the burden of primary headache disorders in Europe

We developed a 103-item self-reporting questionnaire to assess the burden of primary headache disorders on those affected by them, including headache characteristics, associated disability, co-morbidities, disease-management and quality of life. We validated the questionnaire in five languages with 426 participants (131 in UK, 60 in Italy, 107 in Spain, 83 in Germany/Austria, and 45 in France). After a linguistic and a face-content validation, we tested the questionnaire for comprehensibility, internal consistency and test–retest reliability at an interval of one month. In the different countries, response rates were between 73% and 100%. Test–retest reliability varied between –0.27 to 1.0…