Table IV.

Number of patients at risk in each follow-up year, following matching.

	Surgical groups			Non-surgical groups
Year	Lob	Sub	Total cohort	Rad	Obs	Total cohort
0	4,724	4,724	9,448	1,450	1,450	2,900
1	3,895	3,672	7,567	975	736	1,711
2	3,238	2,849	6,087	584	389	973
3	2,623	2,167	4,790	308	214	522
4	2,082	1,640	3,722	174	112	286
5	1,609	1,161	2,770	84	71	155
6	1,202	790	1,992	67	49	116
7	832	523	1,355	23	31	54
8	604	303	907	9	11	20

lob, lobectomy; sub, sublobar resection; rad, radiation; obs, observation.