Statistics
R v. 3.3.1 (R Core Team, 2018) was used
for all statistical tests. Associations of Rh genotype with sex were
measured using a contingency table and the association of these two
factors with physical health problems score and mental
health problems score (which had normal distributions) was tested using
ANCOVA (Type III sum of squares) with the age of subjects as covariate.
Associations of Rh genotype with source health-related variables (which
had mostly highly asymmetric distributions) were measured by a
(nonparametric) partial Kendall correlation test (R package ppcor 1.1
(Kim, 2015)) with age as a covariate.
Correction for multiple tests was done using the Benjamini–Hochberg
procedure with a false discovery rate pre-set to 0.20
(Benjamini & Hochberg, 1995) using the
Excel sheet published by McDonald (2014).