Fig. 5From: 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 treatmentHealth-related economic burden: health care resource utilization.a Results were adjusted for age, sex, country, insurance type, body mass index category, smoking history, alcohol intake, exercise, CCI, PHQ-9, and GAD-7. †P < 0.001, §P = 0.001 vs ≥ 2 preventive treatment failures group. aVisits in the past 6 months. bTraditional providers included pulmonologist, gynecologist, psychologist, etc. CCI, Charlson Comorbidity Index; GAD-7, Generalized Anxiety Disorder-7; PHQ-9; Patient Health Questionnaire-9Back to article page