Impact of headache frequency and preventive medication failure on quality of life, functioning, and costs among individuals with migraine across several European countries: need for effective preventive treatment.

"Declarations Consent for publicationNot applicable. Competing interestsDCB has received grant support and honoraria from AbbVie, Amgen, Biohaven, Collegium, Eli Lilly and Company, Lundbeck, and Teva and for work on the editorial board of Current Pain and Headache Reports. PPR, reports personal fees from AbbVie, Amgen, Biohaven, Chiesi, Eli Lilly, Lundbeck, Medscape, Novartis, Pfizer, and Teva, and grants paid to her research group from AbbVie, AGAUR, Era-Net Neuron, FEDER RIS3CAT, Instituto Investigación Carlos III, International Headache Society, Novartis, and Teva. UR, reports support for the present study paid to his institution from AbbVie; grants from BMBF (German Ministry for Research) and Novartis; personal and institutional fees from AbbVie, Allergan, Eli Lilly, Lundbeck, Medscape, Novartis, Pfizer, StreaMedUp, and Teva. BLB, LL, and AJ are employees of Cerner Enviza and received funding from AbbVie to conduct the study. PG, MP, and LDB are employees of AbbVie and may hold AbbVie stock. Competing interests DCB has received grant support and honoraria from AbbVie, Amgen, Biohaven, Collegium, Eli Lilly and Company, Lundbeck, and Teva and for work on the editorial board of Current Pain and Headache Reports. PPR, reports personal fees from AbbVie, Amgen, Biohaven, Chiesi, Eli Lilly, Lundbeck, Medscape, Novartis, Pfizer, and Teva, and grants paid to her research group from AbbVie, AGAUR, Era-Net Neuron, FEDER RIS3CAT, Instituto Investigación Carlos III, International Headache Society, Novartis, and Teva. UR, reports support for the present study paid to his institution from AbbVie; grants from BMBF (German Ministry for Research) and Novartis; personal and institutional fees from AbbVie, Allergan, Eli Lilly, Lundbeck, Medscape, Novartis, Pfizer, StreaMedUp, and Teva. BLB, LL, and AJ are employees of Cerner Enviza and received funding from AbbVie to conduct the study. PG, MP, and LDB are employees of AbbVie and may hold AbbVie stock."

"Funding Allergan (prior to its acquisition by AbbVie) funded this study and participated in the study design, research, analysis, data collection, interpretation of data, reviewing, and approval of the publication. All authors had access to relevant data and participated in the drafting, review, and approval of this publication. No honoraria or payments were made for authorship."