Table 2.

Accuracy of Alvarado and modified Alvarado scores (Kalan and Al-Fallouji)

Score	Sensitivity	Specificity	PPV	NPV	Accuracy	P
Alvarado	90.3	83.3	96.6	62.5	89.2	0.001
Kelan	90.3	83.3	96.6	62.5	89.2	0.001
Al-Fallouji	96.8	66.7	93.8	80	91.9	0.001

Histological analysis was used as gold standard for diagnosis, Accuracy: True positive + true negative/total number of patients. PPV: Positive predictive value, NPV: Negative Predictive value