416 HAEMOPEXIN LEVELS IN

27

RECOGNISED CARRIERS OF DUCHENNE

MUSCULAR DYSTROPHY

15 years’ exposure, as given in the paper in the reply by Duck and Carter: and al.,

with et

over

by Duck

’

,

Comparison of expected deaths given by Duck et al. and Duck and Carter for duration of exposure greater than 15 years Observed Expected deaths A

All All

41.3 10.99 3.3 4.8

causes cancer

Digestive-system cancer Lung cancer A: from Duck et al.

B 24.2 6.55 2.0 3.0

25 8 4 3

B: from Duck and Carter

The point of the criticism is that it is only valid to compare the observed deaths with those expected in column B, and not those in column A, which was done by Duck et al.

Using all the figures given in the paper’ and the correspondence 23 and applying what appears to us to be reasonable guestimates, gives the following comparison of observed and expected mortality. Reanalysis of data by

duration of exposure and cause of death Duration of exposure