APOH and autoimmune polyendocrinopathy: However only 3 out of 10 positive patients tested positive in assay B. Similarly, in a second cohort of 172 consecutive patients with suspected APS, 22 out of 23 domain I-positive samples were found to be positive in assay A, compared to 19 samples in assay B. From the 149 domain I negative samples, 11 versus 8 samples were shown to be reactive against the coated β2GPI of assay A and B, respectively.