This function allows you to run the Fisher's combined probability test (FCT) method on p-values from GWAS summary statistics, given a variety of parameters.
Arguments
- p
list of numeric vectors. Contains the p-values from each GWAS.
- p_threshold
Numeric scalar (default: 5E-8). The threshold for which we deem an association statistically significant.
- maxval
numeric scalar in range \((0, 1]\) (default: 1). The maximum value for p-values to be considered for analysis.
- fixed
logical (default: TRUE). If the cross-trait association for >1 traits reaches
p_thresholdbut a single trait has the lowest p-value of all combinations, return the result for the >1 traits instead. This is to avoid scenarios where there does seem to be a cross-trait association, but that is suppressed due to statistical properties.
Value
Returns a list with four elements, focused on the optimal subset for each SNP:
p: numeric vector. For each SNP, the p-value of the optimal subset.n: numeric vector. For each SNP, the number of traits in the optimal subset.traits: list of characters. For each SNP, the names of the traits that are in the optimal subset.p_exp: numeric vector. For each SNP, the -log10 p-value of the optimal subset.