Fig. 1

Flowchart of the study. A Overall workflow of the causal inference between migraine and microstructural WM. B Filtering SNP IVs for two-sample MR analysis. C Simplified illustration of Mendelian randomization. Abbreviations: IDPs, imaging-derived phenotypes; GWAS, genome-wide association study; LD, linkage disequilibrium; MAF, minor allele frequency; MR, Mendelian randomization; SNP, single nucleotide polymorphism; WM, white matter