Fig. 2
From: Mid- to late-life migraine diagnoses and risk of dementia: a national register-based follow-up study
Flow chart of the study population selected for analyses (N = 62,578). Data were obtained on 1,657,890 inhabitants in Denmark born between 1935 and 1956. After excluding individuals due to missing information, migraine after age 58, or dementia, death or emigration before entry, 18,135 individuals with migraine diagnoses were matched with 1,378,346 individuals without migraine diagnoses. The matched study population consisted of 105,364 individuals, but also included individuals without information on education and marital status for specific index years and these individuals were therefore excluded after matching leaving 62,578 individuals eligible for analysis