"The reproducibility of the histamine reactions expressed as the standard deviation also revealed significant differences among devices. The variability of the Multi-Test [II] device was significantly less than that of the smallpox needle or the Duotip and DermaPIK by either method as well as the Quintest."
Multi-Test II had the lowest variability of all the devices used (CV = 12.7), including the following:
| Multi-Test II (Avg. combined arm and back) | 12.7 |
| Quintest (Avg. combined arm and back) | 26.4 |
| Smallpox needle (prick) | 22.0 |
| DermaPIK, prick | 19.2 |
| DermaPIK, twist | 16.9 |
This study found DermaPIK twist to be traumatic to the skin, evoking substantial non-specific irritant response. DermaPIK twist had low specificity (35%) at a 3 mm wheal cutoff. Every other method, including DermaPIK prick, was at least 95% specific at a 3 mm level. Sensitivity and specificity for Multi-Test II was 100% and 97.5% respectively.