Day 254 - 22 May 96 - Page 34


     
     1        statistical analysis.
     2
     3   MR. MORRIS:  Can I say, just before we move off the study, the
     4        conclusion at the end is about: "Unlikely that a reduction
     5        in total fat consumption by middle aged and older women
     6        will substantially reduce their risk of breast cancer".
     7        That is after all the variables have been taken away, like
     8        the fibre consumption, and the body mass index, and all
     9        those age at menarche; yes?
    10        A.  What they have done is they have allowed for these
    11        other variables in their analysis.  What they are doing is
    12        they will get groups of women who had a menarche at a
    13        certain age, who have developed breast cancer subsequently,
    14        and a group of women of menarche at the same age who have
    15        not, and they will be compared.
    16
    17        What they are actually doing is trying to relate all of
    18        these other factors to one another so that they get equal
    19        groups of women in the final analysis to try to exclude
    20        what influence these other variables might have on the risk
    21        of developing breast cancer.  At the end of the day, the
    22        single variable that remains is fat intake.  They make the
    23        comment in the paper about the amount of computing time
    24        that was needed for this.  It is a complex issue.
    25
    26   MR. JUSTICE BELL:  Yes. Is there anything more on that article?
    27
    28   MS. STEEL:   Not on the actual document itself.
    29
    30        (To the witness):  Where you say on page 5 of your
    31        statement referring to the study that:
    32
    33        "The authors rightly point out that the deficiencies of
    34        dietary analysis and methodological problems associated
    35        with international case control studies and also indicate
    36        that prospective studies too have been criticised as
    37        misleading because of the size of individual studies, the
    38        limited range of fat intake, and the population studied and
    39        miss-classifications of fat intake", they were only
    40        examining in this paper the cohort studies, were they not?
    41        A.  They were.  I think they fairly point out they are
    42        trying to be impartial too.  I do not think they have a
    43        particular axe to grind.  They are pointing out the
    44        limitations of the studies as they exist today, not only
    45        the international population studies, the case control
    46        studies, but also the cohort studies.  I think they are
    47        being very fair in that respect.
    48
    49   MR. JUSTICE BELL:  Some of the confounding variables, presumably
    50        the Gold Standard, as I think they call it, is more 
    51        reliable than others anyway? 
    52        A.  Yes. 
    53
    54   Q.   People's accounts of their alcohol intake are notoriously
    55        unreliable but they all know whether they have got to
    56        graduation and whether they went beyond the regulation?
    57        A.  Indeed yes.
    58
    59   MS. STEEL:  On page 6 of your statement, the first paragraph,
    60        where you talk about:

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