Table 2.

Selection of lung cancer patients.

	Staging	Number of cases	Average age		Staging	Number of cases	Average age
Observation group	1	48	Twenty-two	Control group	1	33	18
	2	59	26		2	29	Twenty-four
	3	62	25		3	36	Twenty-three
	4	61	31		4	41	Twenty-two
	5	48	37		5	40	26