Table 1.

Operating characteristics for the white blood cell count as a predictor of appendicitis.

Author	Subjects	WBC count (10,000 cell/mm3)	Sensitivity (%)	Specificity (%)	+LR	−LR	AUC (Accuracy)	Study type	Comments
Agrawal et al.27 (2008)	145	≥11	79	55	1.76	0.38		Prospective
Al-gaithy37 (2012)	456	≥9.4	77	66	2.26	0.35	0.70	Retrospective
Andersson et al.28 (1999)	502	≥10	78	68	2.44	0.33	0.80	Observational
Andersson2 (2004)	3382	≥10	83	67	2.52	0.26		Meta-Analysis: 14 studies
		≥15	25	93	3.57	0.81
Deballon et al.41 (2008)	135	≥9.6	86	43	1.51	0.33	0.75	Prospective
Fergusson et al.39 (2002)	1013	≥12	74	72	2.64	0.36	0.80	Retrospective
Keskek et al.29 (2007)	540	≥10.5	84	53	1.79	0.30		Retrospective
Khan et al.30 (2004)	259	≥11	83	62	2.18	0.27		Retrospective
Kharbanda et al.40 (2011)	280	≥14.6	68	80	3.4	0.4	0.78	Prospective	Patients age 3–18
Mentes et al.31 (2012)	201	≥11.9	72	77	3.13	0.36	0.72	Retrospective
Ng et al.32 (2002)	282	≥11	82	39	1.34	0.46		Retrospective
Sengupta et al.33 (2009)	98	≥11	65	72	2.32	0.49		Prospective
Shaw et al.45 (2011)	297	≥11	70, 71	82, 55	3.9, 1.6	0.37, 0.53		Retrospective Cohort	Study performed at 2 different hospitals. Results listed for each hospital
Wu et al.25 (2012)	144	≥11	80	71	2.76	0.28		Retrospective
Xharra et al.34 (2012)	173	≥10	85	68	2.66	0.22	0.83	Prospective
Yang et al.47 (2006)	897	10.4	86	32	1.26	0.44		Retrospective
Yidrim et al.42 (2006)	85	≥12.4	87	64	2.42	0.2	0.84	Retrospective
Yu et al.36 (2012)	1011	Elevated (pooled)	62	75	2.48	0.51	0.72	Meta-analysis: 7 studies

WBC, white blood cell; LR, likelihood ratio; AUC, area under curve