Table 11.

Trends in the mean number of films per X-ray examination in childhood cancer cases and controls according to birth year and age at death for cases and corresponding age for matched controls

	Film Number per examination in birth year cohorts
Age at Death of Cases & Corresponding Age for Controls	1940–47	1948–57	1958–65	1966–69
Cancer Cases
0 - 5	---	2.3	1.7	1.4
6 - 9	3.1	2.4	1.5	1.3
10 - 15	2.1	1.7	1.4	1.0b
All Ages	2.6	2.2	1.6	1.3
Controls
0 - 5	---	2.2	1.4	1.5
6 - 9	1.6	2.1	1.3	1.5
10 - 15	1.7	2.0	1.2	1.5a
All Ages	1.7	2.1	1.4	1.5

Source: Mole 1990 [37] and Gilman et al [83]

^aBased on small numbers