Effect of DDAVP on COAT platelet formation. (A) COAT platelets at baseline (15.9%), 2 hours (24.5%), and 4 hours (30.6%) after DDAVP in a typical patient. For comparison, COAT platelets of the normal control (22.3%) are shown. (B) Relative COAT platelet increase in responding patients (n = 37 of 52 at 2 hours; n = 45 of 52 at 4 hours; P < .001 for both comparisons). Box plots in 4B visualize the median value (horizontal line within the box), the 25th and 75th percentiles (lower and upper borders of the box), the 10th and 90th percentiles (lower and upper whiskers), and each outlier outside the 10th and 90th percentiles (black circles).