. 2012 Mar 24;36(7):1540–1545. doi: 10.1007/s00268-012-1521-4

Table 2.

Patient characteristics

	AIR cohort	Present cohort
	(n = 545)	(n = 941)
Male/female	250 (46%)/295 (54%)	410 (44%)/531 (56%)
Mean age, years	25	32
No. of patients with appendicitis	191 (35%)	346 (37%)
Phlegmonous	117 (22%)	244 (26%)
Advanced	74 (14%)	102 (11%)
No. of patients who underwent surgery	250 (46%)	435 (46%)
Negative appendectomy (at surgery)	59/250 (24%)	89^a/426 (21%)

^aNegative appendectomy consists of patients with no appendicitis at pathological examination (n = 41), patients with an alternate diagnosis (n = 48)