A second strength of our study is that, by contrast with most previous studies in which participants have been selected on the basis of G6PD genotype, we minimised the possibility of misclassification of G6PD deficiency through earlier studies32 in which we established that the G6PD c.202T allele is the only substantial determinant of G6PD deficiency in our study population.5 This evidence concerns the gene G6PD and G6PD deficiency.