Day 036 - 13 Oct 94 - Page 19


     
     1        mentioned.
     2
     3   Q.   In which table?
     4        A.  We were just looking at line 2 of table 4?
     5
     6   Q.   Lines 1 and 2.
     7        A.  OK.
     8
     9   MR. JUSTICE BELL:  Explain your point in relation to saturated
    10        fat.
    11        A.  Without belabouring it, the P value refers to the
    12        probability that the result is by chance alone.  A high
    13        number there is suggestive that it was simply chance.
    14
    15   MR. RAMPTON:  A high number?
    16        A.  Yes.
    17
    18   MR. JUSTICE BELL:  Yes, because it would be, for instance,
    19        there would be a -- we have had lots of Ps of .05?
    20        A.  Yes, .05 or .01.
    21
    22   Q.   So, there is a 5 per cent chance that it is just chance
    23        rather than any factor at all?
    24        A.  That is exactly right.
    25
    26   Q.   You see .71 you are saying there?
    27        A.  Yes, .71; that implies that this is probably a chance
    28        association, or not necessarily chance but that simply the
    29        study was not designed to answer that question in a
    30        meaningful way.  It does not mean it is a poorly designed
    31        study.  It simply means it does not respond to that
    32        question.
    33
    34   MR. RAMPTON:  Yes, but you get a P value of .29 for the total
    35        fat residual in the same table, do you not?
    36        A.  Yes, you do.
    37
    38   Q.   Can I ask you to look at ----?
    39        A.  But probably the only one of these -- just a quick
    40        glancing over these, the only one than would be considered
    41        statistically significant by which most authorities would
    42        say a P less than or equal to .05 appears in table 3 from
    43        polyunsaturate.
    44
    45   MR. RAMPTON:  Yes, exactly.  You will see, when we look at the
    46        discussion, that the authors of this report recognise some
    47        of these difficulties.  The discussion begins on 1095,
    48        which is two pages before the tables, those tables
    49        anyway.  It says:  "Our results indicate a nonsignificant
    50        positive association between dietary fat and risk of 
    51        postmenopausal breast cancer.  In some analyses, the 
    52        strongest association was seen with polyunsaturated 
    53        fat".
    54        A.  I am with you.
    55
    56   Q.   I will read it again.  The discussion begins at the bottom
    57        of the left-hand column:  "Our results indicate a
    58        nonsignificant positive association between dietary fat
    59        and risk of postmenopausal breast cancer.  In some
    60        analyses, the strongest association was seen with

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