Summary Statistics
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Heavy Menstrual Bleeding summary statistics (Thibord et al., Blood 2025)  

Summary statistics were generated for:
 - Discovery meta-analysis (All Of Us, MVP, Finngen, Estonia Biobank)
 - African-specific ancestry meta-analysis (All Of Us, MVP, UK Biobank)
 - European-specific ancestry meta-analysis (All Of Us, MVP, Finngen, Estonia Biobank, UK Biobank)
 - Hispanic-specific ancestry meta-analysis (All Of Us, MVP)
 - ALL combined meta-analysis (All Of Us, MVP, Finngen, Estonia Biobank, UK Biobank)

The cohort order indicated here between parentheses corresponds to the order given in the 'Direction' column.


Methods:
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Each study conducted GWAS with logistic regression, adjusted at least for age and PCs. Low imputation quality variants (<0.3) were discarded before conducting fixed-effects IVW meta-analyses with METAL. Variants with minor allele frequency < 1% were discarded, as well as variants present in only one of the meta-analyzed studies.


Header description:
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The summary statistics corresponds mostly to the raw output of METAL, with the addition of columns indicating chromosome, position, number of cases, and number of controls:

 - CHR : Chromosome
 - POS : Position (build hg38)
 - MarkerName : unique identifier for each variant built as CHR:POS:A1:A2 (where A1 and A2 do not necessary match the Allele1 and Allele2 columns generated by METAL)
 - Allele1 : Effect Allele
 - Allele2 : Non Effect Allele
 - Freq1 : Frequency of Effect Allele (average across studies)
 - FreqSE : Standard Error of Freq1 distribution between different studies included (see 'Direction' column to infer studies that had the variant)
 - Effect : Effect observed for Allele 1 (corresponds to log(OR))
 - StdErr : Standard Error
 - P-value : P-value
 - Direction : Direction of effect in each study (see top of this readme to know order)
 - HetISq : Heterogeneity I-square
 - HetChiSq : Heterogeneity test (Cochran's Q)
 - HetDf : Heterogeneity degree of freedom (number of study - 1)
 - HetPVal : Heterogeneity P-value
 - N_CASES : Number of cases
 - N_CONTROLS : Number of controls