. Author manuscript; available in PMC: 2015 Dec 1.

Published in final edited form as: JAMA Otolaryngol Head Neck Surg. 2014 Dec 1;140(12):1101–1109. doi: 10.1001/jamaoto.2014.2530

Table 2.

Head and Neck Melanoma Disease-Specific Mortality Hazards for SLNB Compared to Nodal Observation in Propensity-Score Matched-Pair Cohorts

Cohort^a	Number of matched pairs	DSS
Cohort^a	Number of matched pairs	HR^b	CI^c	p^d
All	2551	0.94	0.77-1.15	0.57

Thin	552	1.53	0.75-3.13	.24
Intermediate	1404	0.87	0.66-1.14	.31
Thick	354	0.80	0.56-1.15	.23

Each cohort underwent separately performed propensity-score matching

Based on Cox proportional-hazards model with a robust sandwich covariance estimator

95% confidence interval for the hazard ratio

p-value for Cox proportional hazards test, where values <0.05 are considered significant

Abbreviations: SLNB=sentinel lymph node biopsy; HR=hazard ratio; CI=confidence interval; DSS=melanoma disease-specific survival; Thin=Breslow depth 0.75-1mm; Intermediate=Breslow depth 1-4mm; Thick=Breslow depth >4mm