Table 2.

Studies that showed no statistically significant relation between provider caseload and survival in breast cancer patients

Author	Patients, n	Stage	Hospital, case volume	Surgeon, case volume	Odds ratio, death	95% CI	Year(s) of treatment	Country
Twelves et al. 2001 [31]	1,617	M0	1–9		1.07	0.83–1.37	1987	Scottland
			10–29		1.11	0.91–1.35
			≥30		1.0
Nattinger et al., 2007 [22]	12,216	I, II		<5	1		1994–1996	USA
		>66 years		5–9	1.0	0.84–1.20
				>10	0.94	0.76–1.16