Performance of several risk scores for infectious syphilis among MSM; Amsterdam Centre for Sexual Health, July 2018–July 2019
| Risk score* | Cut-off† | Infectious syphilis among those with a score of at least the cut-off | Infectious syphilis among those with a score below the cut-off | Sensitivity (95% CI) | Specificity (95% CI) | AUC | % to be tested |
| Score A1 | 1.0 | 220/1,270 | 318/20,376 | 40.9 (36.7 to 45.2) | 95.0 (94.7 to 95.3) | 0.6811 | 5.9 |
| Score A2 | 0.9 | 220/1,226 | 318/20,420 | 40.9 (36.7 to 45.2) | 95.2 (94.9 to 95.5) | 0.6846 | 5.7 |
| Score B1 | 1.0 | 218/1,206 | 320/20,440 | 40.5 (36.3 to 44.8) | 95.3 (95.0 to 95.6) | 0.6811 | 5.6 |
| Score B2 | 1.5 | 218/1,206 | 320/20,440 | 40.5 (36.3 to 44.8) | 95.3 (95.0 to 95.6) | 0.6846 | 5.6 |
| Score C1 | 1.0 | 218/1,206 | 320/20,440 | 40.5 (36.3 to 44.8) | 95.3 (95.0 to 95.6) | 0.6811 | 5.6 |
| Score C2 | 1.5 | 218/1,206 | 320/20,440 | 40.5 (36.3 to 44.8) | 95.3 (95.0 to 95.6) | 0.6846 | 5.6 |
*Risk scores are based on the multivariable models as explained in table 2. Risk scores A1, B1 and C1 are based on a summation of all risk factors, each with identical weight (one). Risk scores A2, B2 and C2 are based on a summation of the weights of all risk factors, the weight being identical to the regression coefficient of a factor in the multivariable model (see table 2).
†Based on the Youden Index.
AUC, area under the curve; MSM, men who have sex with men.