Validation of the use of questionnaire-based surveys for identification of psoriasis
| Sensitivity (%) | 95% CI | Specificity (%) | 95% CI | LR+ | 95% CI | LR- | 95% CI | |
| Patient-reported psoriasis (regardless of whether or not this was diagnosed by a physician) | 84.4 | 83.2 to 85.5 | 88.2 | 87.1 to 89.2 | 7.14 | 6.54 to 7.80 | 0.18 | 0.16 to 0.19 |
| Patient-reported physician diagnosed psoriasis | 83.3 | 82.2 to 84.5 | 91.8 | 90.8 to 92.6 | 10.11 | 9.08 to 11.26 | 0.18 | 0.17 to 0.20 |
| Patient-reported dermatologist diagnosed psoriasis | 78.8 | 77.6 to 80.10 | 93.6 | 92.8 to 94.4 | 12.31 | 10.90 to 13.91 | 0.23 | 0.21 to 0.24 |
True positive cases were drawn from Sample B. True negative cases were drawn from Sample C.
Sensitivity = true positive / (true positive + false negative).
Specificity = true negative / (false positive + true negative).
LR+ = sensitivity / (1 – specificity).
LR- = (1 – sensitivity) / specificity.
LR+, positive likelihood ratio; LR-, negative likelihood ratio.