Table 4.

Factors associated with high-volume surgeon status

	Characteristic	Coefficient (95% CI)
Age group	20-29	Reference
	30-39	1.9 (1.2, 2.5)
	40-49	5.3 (4.7, 6.0)
	50-59	5.5 (4.8, 6.1)
	60-69	3.5 (2.8, 4.1)
	>=70	1.8 (1.1, 2.6)
Sex	Female	Reference
	Male	1.7 (1.3, 2.0)
Surgical specialty	General surgery	Reference
	Cardiothoracic Surgery	−3.5 (−6.2, −0.7)
	Colorectal Surgery	−1.8 (−2.9, −0.8)
	Hand Surgery	10.7 (9.8, 11.6)
	Neurosurgery	2.2 (1.6, 2.8)
	Ophthalmology	−3.1 (−3.7, −2.6)
	Orthopedics	12.8 (12.5, 13.2)
	Otolaryngology	−2.1 (−2.6, −1.7)
	Pediatric Surgery	−2.1 (−3.1, −1.1)
	Plastic Surgery	−0.6 (−1.1, −0.1)
	Thoracic Surgery	−2.1 (−2.9, −1.4)
	Transplant Surgery	−1.9 (−4.3, 0.5)
	Urology	−1.3 (−1.7, −0.8)
	Vascular Surgery	−1.9 (−2.6, −1.2)
Urban/rural practice location	Urban	Reference
	Rural	0.1 (−0.9, 1.1)
Region	Northeast	Reference
	Midwest	2.9 (2.5, 3.2)
	South	6.1 (5.8, 6.5)
	West	0.8 (0.4, 1.2)
Number of physicians in practice	1	Reference
	2-5	0.9 (0.3, 1.4)
	6-9	0.3 (−0.3, 0.9)
	10-19	1.2 (0.7, 1.9)
	20-50	2.1 (1.5, 2.7)
	51-99	0.6 (−0.2, 1.3)
	>=100	−1.0 (−1.6, −0.5)
Academic affiliation	No	Reference
	Yes	−0.8 (−1.3, −0.4)
Affiliated with health system	No	Reference
	Yes	−1.6 (−2.0, −1.1)