Table 6.

Diagnostic properties at the low probability zone

Characteristics	AIR score 0–4
	Complicated appendicitis
	NPV	95% CI	p-value	Sensitivity	95% CI	p-value
All patients	99	98–100		99	98–100
Patients sex			0.042			0.48
Women	100	99–100		99	98–100
Men	98	97–100		98	97–100
Patients age			0.44			0.85
<15 years	99	97–100		98	94–100
15–39 years	99	98–100		98	97–100
≥40 years	99	97–100		99	98–100
Duration of symptoms			0.46			0.10
<12 h	99	98–100		97	94–100
12–23 h	98	96–100		98	96–100
24–47 h	99	98–100		100	99–100
>47 h	99	98–100		99	97–100
Examiners competence			0.52			0.87
Interns	99	98–100		99	97–100
Residents	99	98–100		99	98–100
Specialists	98	96–100		98	95–100

NPV and sensitivity for complicated appendicitis is presented as not missing complicated appendicitis is most important to safely practice observation