The Lancet Weight Determines Wheal Diameter in Response to Skin Prick Testing with Histamine - Fig 2

<p><b>A)</b> The mean wheal diameters on the forearms for each lancet weight; 25 g, 85 g, 135 g and 265 g. A higher lancet weight significantly increased the sizes of the wheal reactions. <b>B)</b> The mean wheal diameters on the back for each lancet weight; 25 g, 85 g, 135 g and 265 g. A higher lancet weight significantly increased the sizes of the wheal reactions. A significant difference was also observed when comparing the two histamine concentrations: 1 mg/mL and 10 mg/mL. For each condition; n = 20. * = p < 0.05, ** = p < 0.01. Mean ± SEM.</p

Weighted SPT lancet device.

<p>Depicts a suggested mechanical approach to a locked weight device allowing for SPT within a specific predetermined weight.</p

The mean and coefficient of variation (CV %), calculated as the ratio between the standard deviation and the mean for the four predetermined peak lancet weights; 25 g, 85 g, 135 g and 265 g at the forearm and back.

<p>Data for applied lancet weight are pooled for conditions with saline, 1 mg/mL of histamine and 10 mg/mL of histamine. Notice that the deviation is proportionally higher in the 25 g weight group.</p