Table 3.

Ultrasound findings to discriminate appendicitis from non-appendicitis in backward elimination logistic regression analysis

Variables	Frequency (60)a		Odds ratio	95% confidence interval	p-value
Appendix wall thickness (2 mm)b	45	Reference
15
Increased wall flow in appendix			18.0	3.09, 104.6	0.001
No	42	Reference
Yes	18
Appendix mucosal discontinuity
No	53	Reference
Yes	7
Non-compressibility of appendix			12.7	2.45, 66.23	0.002
No	24
Yes	36
Probe tenderness over the appendix
No	39	Reference
Yes	21
Periappendiceal increased echo
No	53	Reference
Yes	7

^aThe number in parentheses is the total number of cases used in this analysis. Two cases among the enrolled patients were excluded owing to the non-visualization of appendix in ultrasound re-evaluation.

^bThe optimal cut-off value for discrimination of appendicitis was obtained by the receiver operating characteristic curve and Youden index.