Risk factor | Score if present | ||
SS, SC, other or unknown variant | +1 | ||
Chest pain | +1 | ||
Chills | +1 | ||
Pain not similar to previous episodes | +1 | ||
Temperature <36°C or >38°C | +1 | ||
Oxygen saturation <95% | +1 | ||
Haemoglobin <10 | +1 | ||
Nitrites present on urinalysis | +1 | ||
Abnormalities observed on chest x ray | +1 | ||
Total possible score | 9 |
Score >2 | Score >4 | Physician judgement | |
Overall accuracy | 61.7 (54.8 to 68.2) | 82.7 (76.8 to 87.4) | 81.8 (75.8 to 86.6) |
Sensitivity | 86.0 (73.7 to 93.3) | 49.1 (35.8 to 62.6) | 77.2 (63.8 to 86.8) |
Specificity | 52.9 (44.8 to 60.8) | 94.9 (89.9 to 97.6) | 83.4 (76.5 to 88.7) |
False negative rate | 14.0 (6.7 to 26.3) | 50.9 (37.4 to 64.2) | 22.8 (13.2 to 36.2) |
False positive rate | 47.1 (39.2 to 55.2) | 5.1 (2.4 to 10.1) | 16.6 (11.3 to 23.5) |
Positive predictive value | 39.8 (31.2 to 49.1) | 77.8 (60.4 to 89.3) | 62.9 (50.4 to 73.9) |
Negative predictive value | 91.2 (82.9 to 95.9) | 83.7 (77.3 to 88.6) | 91.0 (84.8 to 94.9) |
SC, sickle cell haemogoblin C disease; SS, homozygous sickle cell disease.
SC, sickle cell haemogoblin C disease; SS, homozygous sickle cell disease.