Table 1.

Subject characteristics

Characteristics	Groups		p-value
	US (n=18)	LM (n=18)
Sex			1,000a
Male	3 (16.7%)	2 (11.1%)
Female	15 (83.3%)	16 (88.9%)
Age (years)	42.4±14.4	45.9±16.5	0.502b
BMI (kg/m2)	23.6 (16–26.5)	21.8 (20–35)	0.679c
ASA physical status			0.278d
ASA I	7 (38.9%)	4 (22.2%)
ASA II	11 (61.1%)	14 (77.8%)

Notes: Values are expressed as mean ± SD or median (minimum–maximum) for numerical data and frequency (%) for categorical data; n = number of subjects;

^aFisher’s exact test;

^bIndependent t-test;

^cMann–Whitney U-test;

^dχ² test.

Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; LM, landmark; US, ultrasound.