Day 254 - 22 May 96 - Page 25
1 of them are in middle life?
2 A. Indeed. I suppose in many respects what these studies
3 have tried to do is to look at women during a period of
4 time when they are most likely to develop breast cancer.
5
6 Q. Because you are most likely to get rewarding results, if
7 that is not an unfortunate way of expressing it?
8 A. If you start looking at women in their 20s ----
9
10 MR. JUSTICE BELL: You want to get as big a return for your
11 efforts as you possibly can?
12 A. You would certainly need to follow them up for 30 to 40
13 years to find out exactly what does happen to these women
14 throughout their life time, indeed.
15
16 Q. As you said before, that is one of the difficulties?
17 A. Yes, but in fact ----
18
19 Q. With all these studies, is the timescales?
20 A. It is, indeed. If we go back to, I think it was Doll,
21 one of Doll's original findings -- I think about 1975,
22 I cannot remember the exact date -- when they looked at
23 diet 30 years previously and diet now, they thought in
24 their original hypothesis that the current diet was more
25 important than the previous diet. Now, whether that really
26 is the case or not I do not think we can say because it may
27 well be previous diet which is more important, and I think
28 that is possibly why these studies were established
29 because, as you will see, some of them started in the 70s
30 or early 80s, not long after the original hypothesis was
31 stated.
32
33 Q. No, just that everyone is aware of it, one of the
34 difficulties, or the potential difficulties, to me with all
35 these studies is that they generally cover people in a
36 limited period of middle life when the great majority of
37 the customers of the Plaintiffs are eating their food, or
38 significant amounts of their food, if they eat significant
39 amount of their food, it may be argued at an earlier age.
40 We do not start, as I have already pointed out, until 28,
41 and then the next group is 34, and then we get 3 groups
42 which start at 40. But that, I suppose, is just a
43 limitation on virtually all the work which has been done in
44 this area?
45 A. Indeed, yes, my Lord, and in fact on page 8 of my
46 report ----
47
48 Q. So, save for the population studies?
49 A. Yes. My report at page 8 on the third paragraph
50 I quote from Hill in the European Journal of Cancer
51 Prevention where he makes this very point, that a
52 limitation is the long follow-up period which is necessary,
53 in order to avoid the study simply measuring the causation
54 of late stage events.
55
56 Q. Population studies, the comment I have made does not apply
57 to in that you are looking at the instance of various
58 degenerative diseases in the population and, of course, the
59 population has to be born and lived through its early
60 years, so that does not apply to the population studies,
