G6PD and G6PD deficiency: This study highlights the influence of blood disorders on the performance of a point-of-care test for G6PD deficiency, the STANDARD G6PD Test; the performance of the same test conducted at the point of care on non-anticoagulated capillary blood and venous K2EDTA blood across three sites in the United States; and the limitations of interlaboratory reference G6PD comparison, specifically normalization.