Table 5

Sensitivity checks for surgical margins, 90 days re-excision and overall survival

	Surgical margins† (0=margins free, 1=focally positive)		90 days re-excision‡ (0=no re-excision, 1=re-excision)		Overall survival§
	OR	P value	OR	P value	HR	P value
Hospital volume (rolling average as continuous variable) Number of other hospitals in the proximity of hospital i in 30 km radius (continuous variable)	0.99	0.60	0.99	0.09	0.99	0.00**
	0.99	0.72	0.98	0.03*	0.99	0.01*
Hospital volume (absolute volume as continuous variable) Number of other hospitals in the proximity of hospital i in 30 km radius (continuous variable)	0.99	0.61	0.99	0.07	0.99	0.00**
	0.99	0.72	0.98	0.03*	0.99	0.01*
Hospital volume (rolling average as continuous variable, scaled by IQR) Number of other hospitals in the proximity of hospital i in 30 km radius (continuous variable, scaled by IQR)	0.96	0.57	0.89	0.07	0.97	0.00**
	0.98	0.71	0.87	0.03*	0.97	0.01*
Hospital volume (absolute volume as continuous variable, scaled by IQR) Number of other hospitals in the proximity of hospital i in 30 km radius (continuous variable, scaled by IQR)	0.96	0.62	0.89	0.07	0.97	0.00**
	0.98	0.72	0.87	0.03*	0.97	0.01*
Hospital volume (rolling average as continuous variable, scaled by IQR) Number of other hospitals in the proximity of hospital i in 20 km radius (continuous variable, scaled by IQR)	0.95	0.55	0.89	0.08	0.97	0.00**
	0.95	0.45	0.88	0.08	0.97	0.00**
Hospital volume (rolling average as continuous variable, scaled by IQR) Number of other hospitals in the proximity of hospital i in 40 km radius (continuous variable, scaled by IQR)	0.96	0.58	0.89	0.07	0.97	0.00**
	0.99	0.98	0.87	0.05	0.97	0.02*

*P<0.05; **p<0.01.
†Logistic regression with clustered SEs. Corrected for age, socioeconomic status, morphology, TNM stage, tumour grade, hospital type, year of surgery.
‡Logistic regression with clustered SEs. Corrected for age, socioeconomic status, surgical procedure morphology, TNM stage, tumour grade, hospital type, year of surgery.
§Multilevel Cox proportional hazards model with hospital and year of surgery random effects, corrected for age, socioeconomic status, surgical procedure, morphology, TNM stage, tumour grade, hormone status, neoadjuvant chemotherapy, hospital type, year of surgery.
TNM, tumour, node, metastases.