Table 5.

Results

Independent variable	Odds Ratio (95% CI)	p
Core needle passes per patient	*	0.04
Core needle gauge	**	0.99
Patient BMI	*	0.69
Patient BMI ≥30	0.93 (0.21–4.80)	0.99
Skin-to-tumor distance	*	0.95
Skin-to-tumor distance ≥7 cm	0.59 (0.14–2.48)	0.52
Thickness of subcut. fat	*	0.98
Thickness of subcut. fat ≥3 cm	0.59 (0.14–3.07)	0.47
Involvement of a trainee	1.46 (0.33–6.00)	0.53
Kidney laterality	0.99 (0.24–4.37)	0.99
Cortical location	***	0.83
Endophytic vs. exophytic	***	0.99
Mass size (cm)	*	0.30
Mass size <4cm	1.36 (0.25–14.08)	0.99
Enhancement (<20HU)	**	0.99
Cystic	*	0.83

*Numeric variable, therefore Wilcoxon two-sample rank-sum test was used for significance testing and the odds ratio was not calculated for individual pairs

**Insufficient data to run formal significance testing on this variable

***Odds Ratio was not calculated for individual pairs