Table 2. Demographic data, smoking habits, and work-related data of male lymphohaematopoietc cancer cases and a subcohort of non-cases among Norwegian offshore oil industry workers.

	Casesa		Non-cases
	N	%	N	%
Total	112	100	1661	100
Year of birth
1915–1919	0	0.0	3	0.2
1920–1924	0	0.0	31	1.9
1925–1929	5	4.4	141	8.4
1930–1934	10	8.9	129	7.8
1935–1939	12	10.7	221	13.3
1940–1944	18	16.1	397	23.9
1945–1949	20	17.9	323	19.5
1950–1954	13	11.6	110	6.6
1955–1959	20	17.9	172	10.3
1960–1964	10	8.9	88	5.3
1965–1969	4	3.6	29	1.8
1970–1974	0	0.0	10	0.6
1975–1979	0	0.0	7	0.4
First employment offshore
1965–1969	4	3.6	48	2.9
1970–1974	12	10.7	187	11.3
1975–1979	43	38.4	621	37.4
1980–1984	22	19.6	348	20.9
1985–1989	22	19.6	284	17.1
1990–1994	5	4.5	115	6.9
1995–1998	4	3.6	58	3.5
Other benzene exposureb
Yes	19	17.0	300	18.1
No	93	83.0	1361	81.9
Ever daily smoker
Yes	80	71.4	1190	71.6
No	24	21.5	349	21.0
Unknown	8	7.1	122	7.4

^aAll lymphohaematopoietc cancer cases.

^bBenzene exposure from other work (before, after, and in-between offshore work).