Table 1. Baseline characteristics and type of surgery.

	Entire cohort (n=14,894)		Mastectomy and no reconstruction (n=9,250)		Mastectomy and immediate implant-based reconstruction (n=3,007)		Mastectomy and immediate autologous reconstruction (n=2,637)		P*
	N	Column %	N	Row %	N	Row %	N	Row %
Age at diagnosis (years)									<0.001
< 40	1122	7.5	453	40.4	405	36.1	264	23.5
40-49	4378	29.4	2209	50.5	1203	27.5	966	22.1
50-59	7378	49.5	4997	67.7	1162	15.8	1219	16.5
60 and older	2016	13.5	1591	78.9	237	11.8	188	9.3
Year of mastectomy									<0.001
1998	381	2.6	258	67.7	30	7.9	93	24.4
1999	592	4.0	394	66.6	59	10.0	139	23.5
2000	608	4.1	410	67.4	58	9.5	140	23.0
2001	874	5.9	566	64.8	118	13.5	190	21.7
2002	1362	9.1	935	68.7	190	14.0	237	17.4
2003	1749	11.7	1166	66.7	328	18.8	255	14.6
2004	1779	11.9	1088	61.2	321	18.0	370	20.8
2005	1829	12.3	1109	60.6	385	21.1	335	18.3
2006	2537	17.0	1547	61.0	592	23.3	398	15.7
2007	3183	21.4	1777	55.8	926	29.1	480	15.1
Relationship with employer									0.26
Employee	8698	58.4	5372	61.8	1765	20.3	1561	18.0
Spouse	6177	41.5	3863	62.5	1238	20.0	1076	17.4
Unknown	19	0.1	15	79.0	4	21.1	0	0.0
HMO or PPO with capitation									<0.001
No	12063	81.0	7506	62.2	2366	19.6	2191	18.2
Yes	2831	19.0	1744	61.6	641	22.6	446	15.8
Region of country									<0.001
Northeast	1180	7.9	624	52.9	251	21.3	305	25.9
North Central	3802	25.5	2360	62.1	863	22.7	579	15.2
South	7234	48.6	4433	61.3	1321	18.3	1480	20.5
West	2456	16.5	1683	68.5	544	22.2	229	9.3
Bilateral mastectomy									<0.001
No	13160	88.4	8625	65.5	2229	16.9	2306	17.5
Yes	1734	11.6	625	36.0	778	44.9	331	19.1
Lymph node surgery									<0.001
No	2592	17.4	1277	49.3	721	27.8	594	22.9
Yes	12302	82.6	7973	64.8	2286	18.6	2043	16.6
Chemotherapy									<0.001
No	7084	47.6	3846	54.3	1754	24.8	1484	21.0
Before surgery	1372	9.2	1026	74.8	164	12.0	182	13.3
After surgery	6438	43.2	4378	68.0	1089	16.9	971	15.1
Radiation									<0.001
No	9675	65.0	5191	53.7	2459	25.4	2025	20.9
Yes	5219	35.0	4059	77.8	548	10.5	612	11.7

^*- chi-square test