Table 8

Table 8 --Comparison of Several CT Studies for the Diagnosis of Appendicitis

Author	Year	Contrast	Helical	n	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)
Balthazar et al. [139]	1991	Oral IV	No	100	98	83	91	97
Malone et al. [140]	1993	No oral No IV	No	211	87	97	94	93
Balthazar et al. [141]	1994	Oral IV	No	100	96	89	96	95
Lane et al. [142]	1997	No oral No IV	Yes	109	90	97	95	95
Rao et al. [143]	1997	Oral Rectal No IV	Yes	100	100	95	97	100

PPV = positive predictive value; NPV = negative predictive value; n = number of patients studied. [34]