Errors and Omissions in Experimental Trials - 2c
CHAPTER 20
Further criticisms and comments.
In the second edition of the
monograph Fluoridation. Errors and Omissions in Experimental Trials it
was stated that copies of the first edition were sent by the Federal
President of the Australian Dental Association to all the men in charge
of the trials which had been considered.
As has been mentioned, criticisms by
the authors of the Evanston and the Brantford (Canadian Department of
National Health and Welfare) studies, were published as "book
reviews" in the February, 1960, issue of the Australian Dental
Journal.
After the second edition was "in
press", the June 1960 issue of Nutrition Reviews was received,
containing (Vol. 18, pp. 161-165) a paper by Dr J.M. Dunning entitled
"Biased criticism of fluoridation. This paper quoted some passages
from "... letters to Dr Kenneth Adamson, President of the Australian
Dental Association" from the senior author of the Grand Rapids
trial, Dr F.A. Arnold Jr., and from the senior author of the Newburgh
trial, Dr D.B. Ast, and some criticisms by Dr J.R. Blayney of the
Evanston trial, which had not been published in the above-mentioned
"book reviews" in the Australian Dental Journal.
The following pages contain all the
passages from those letters which were published by Dr Dunning. In view
of the title he gave to his paper, it is considered likely that he cited
from those letters the quotations which he considered to be the most
important criticisms advanced by the authors of those fluoridation
trials.
These comments were prepared in 1960
and had a very limited circulation in roneoed form. They have not been
otherwise published until now because of the refusal of many editors to
accept comments which question fluoridation.
Dr F.A. ARNOLD JR
Dr Dunning said that: "Dr F.A.
Arnold, Jr., Director of the National Institute of Dental Research and
principal investigator at Grand Rapids, writes in part as follows (Arnold
to Adamson. October 16. 1959)".
The quotation from Dr Arnold's letter
which will be considered first is the following accusation (as reported
by Dr Dunning):
(84) "Although he [the author of
the monograph] did not publish his material until 1959, he (apparently
intentionally) overlooked the report of the tenth year of the study which
appeared in 1956. As was originally planned, it was this year that we
obtained "complete" age groups of adequate size."
Comment.
It is difficult to believe that Dr Arnold could have made this
extraordinary accusation for, if the monograph is consulted, it can be
seen that "...the report of the tenth year of the study which
appeared in 1956" the paper by Arnold et al. (1956) - was (a) listed under Dr Arnold's own name in
the references, (b) shown, again under his name, in the Index, which
indicates that this paper was mentioned on four pages, and (c) was given
as the source of the data from which Figures 1 and 2 were compiled (pages
147 and 148). These two figures depict the caries rates reported for each
age group in each year in the city of Muskegon up to the time when, as a
result of its water supply having been fluoridated, it ceased to be the
"fluoride-free" control city for Grand Rapids. (See explanatory
notes to Figures 1 and 2, pp. 147 and 148).
If Dr Arnold is correctly quoted by
Dr Dunning, it would appear that, before criticizing it, he read the monograph
only superficially, even that part of it which relates to his own study.
Furthermore, it is clear that, before making the accusation that
"apparently intentionally" this 1956 report from the Grand
Rapids study had been "overlooked", he failed to check both the
list of references and the Index.
If this is not the case, one is
forced to conclude that Dr Arnold made this accusation deliberately,
knowing that it was untrue, with the intention of misleading the
President of the Australian Dental Association.
That author was also reported to have
written (85-91):
(85) "He [Sutton] overlooks the
fact that one examiner has been with the study throughout."
Comment.
This fact was not "overlooked". This can be seen by referring
to the monograph, the top of page 144 where Arnold et al. were quoted as saying that: "There have been
changes in the dental examiners with the exception of one officer who has
participated in each series of examinations. Each new examiner has been
calibrated against this one officer to standardize diagnostic
criteria" (Arnold et al.,
1953).
(86) "If we used his findings,
we would come up with the same general result."
Comment.
As it is unlikely that the findings of this examiner were not used in
this study, it is concluded that Dr Arnold is referring to the situation
which would have arisen if the data from this study had been confined to
those obtained by that one examiner. However, no comment can be made in
this matter as in the published data the findings of the examiners were
combined.
(87) "Also, we could call
attention to the fact that two more of the four examiners used throughout
the first ten years of the study started examining during the third year
of the study and have participated each year since. "
Comment.
Dr Arnold refers to "the four examiners used throughout the first
ten years of the study". However, in a note published on the first
page of his report of the tenth year of the study (Arnold et al., 1956), he stated that:
"The following dental officers of the Public Health Service conduct
the annual dental examinations", and named five examiners: Doctors
Likins, Russell, Scott, Singleton and Stephan. In addition, he mentioned
the names of four other dentists who "also participated as
examiners" in the study: Drs Loe, McCauley, Ruzicka and Short. In
his 1953 report also (Arnold et al.,
1953) he had acknowledged the participation of the same nine examiners
not four as Dr Arnold stated in his misleading letter to the President of
the Australian Dental Association.
(88) "He criticizes our
selecting samples by school grade. If he would realize it, and probably
he does, this strengthens the study."
Comment.
It is evident that Dr Arnold has changed his views on this matter. When,
in 1953, he described the method used (Arnold et al., 1953), he acknowledged that "choosing examinees
by grade in this manner will, in some instances, not give
well-distributed specific age groupings." But now he says that
"... selecting samples by school grade ... strengthens the
study."
(89) "In the first place this
gives us a random sample."
Comment.
In order to be satisfied that the children examined constitute a random
sample of those in the city, it is necessary to know if the children were
a random sample of those in their school and, also, that the schools in
which the examinations were made were a random sample of those in each
city. The method of sampling, as described by Arnold et al. (1953), was stated on page 153. The meagre description
that "on the basis of available information" (which was not disclosed)
" 25 representative schools were selected" - no description of
the method of selection being given - does not permit the reader even to
attempt to determine whether or not the schools selected constituted a
random sample of those in the city. In the next report (Arnold et al., 1956) it was not stated
how many schools were selected, merely that "The annual samples of
the school population of Grand Rapids and Muskegon are taken from schools
selected as representative of each city as a whole." (See comment 91
below for an independent report on the sampling methods used in this
study.)
(90) "Also, it permitted us to
examine all the children of a grade without the examiners knowing whether
the child belonged to the "continuous resident" group or
not."
Comment.
This fact was mentioned by Arnold et
al. in 1953. However, it is of little consequence, for no comparisons
were published between the caries rates in the "continuous
resident" group and the other children in Grand Rapids. This
statement by Arnold indicates that he realized the need for
"blind" examinations. However, he made no attempt to
incorporate this vital point in experimental design when he arranged for
the examination of the Grand Rapids children and their comparison with
those of the control city of Muskegon. The desirable aim of eliminating
unintentional bias on the part of the examiners would have been achieved
if the children in the test and the control cities had been examined on
the same occasions "without the examiners knowing whether the child
belonged to the "continuous resident" group in Grand Rapids or
the "continuous resident" group in the control city of
Muskegon. Unfortunately this was not done.
(91) "The planning of the study
and the analysis of the data were done by a group of people all of whom
are more knowledgeable in this field of research than is Dr Sutton."
Comment.
No comment will be made on this remark (except to say that Dr Arnold has
never met me) but it is pertinent to quote another opinion. T.M.
DeStefano (Bull. Hudson County Dent. Soc, 23: 20-31, Feb. 1954) quotes
from the critique of the report of the "seventh Year of Grand
Rapids-Muskegon Study" (Arnold et
al., 1953) that "... had been sought and paid for by a group of
general practitioners from a reliable statistical firm" (the
Standard Audit and Measurement Services, Inc., 89 Broad St., New York 4,
N.Y ). DeStefano quotes this critique as stating:
"The authors appear to have
demonstrated an unfortunate disdain for some of the pre-requisites of
valid research." Also that "In the first place, the sampling
design of the experiment is embarrassingly conspicuous by its absence.
Such a brief description as: "On
the basis of available information the 31 school districts in Grand
Rapids were classified on a socio-economic basis. From the 79 schools in
those districts, 25 representative schools were selected and the
examiners assigned ... etc." leads one to suspect that the drawing
of the sample was dangerously amateurish. This suspicion makes one feel
that either the results of fluoridation are so dramatic as to force
themselves through the veil of poorly selected samples or "at the
other extreme" that the reported results are merely the fiction of a
biased sample. From work other than that reported by the authors, one
tends to discard the latter possibility but the lack of sophistication
shown in selecting the sample leads to complete bewilderment as to the
precise effects or the extent of the effect of fluoridation."
This critique by the Standard Audit
and Measurement Services continues:
"With a pre-listed population
(such as a school enrolment) there would appear to be no excuse for not
using modern sampling tools and procedures. Employment of these devices
would enable not only a more certain statement of the effects of fluoridation
but (perhaps more importantly) a precise estimate of the error inherent
in such statements."
DR D.B. AST
Dr Dunning then said that "Dr
David B. Ast, Director, Bureau of Dental Health of the New York State
Department of Health, makes the following comments (Ast to Adamson, March
3, 1960)".
Dr Ast is reported to have written
(92-7):
(92) "Sutton criticizes the
comparability of data among the four studies because in Newburgh and
Kingston we used the rate based on DMF per 100 erupted permanent teeth instead
of DMF per child."
Comment.
Contrary to this statement by Dr Ast, "the comparability of data
among the four studies" was not criticized. However, it was pointed
out that it is very difficult to compare the results shown in the five
reports from Dr Ast's Newburgh trial because of the different methods of
presentation of data that were adopted by Dr Ast and his co-workers. Nor
was criticism levelled at the use of "the rate based on DMF per 100
erupted permanent teeth"
(93) "We explained why we used
the permanent tooth population as the universe considered."
Comment.
The paper giving this explanation (Ast et al., 1956) was referred to on twelve pages of the
monograph.
(94) "However, in order to make
our data comparable to other study data, in the reports for 1953-54 and
1954-55, the Newburgh-Kingston data were given both ways - DMF per 100
teeth, and DMF per child."
Comment.
If the aim of Dr Ast and his co-workers was to make the data from their
study "comparable to other study data", it is unfortunate that
they did not examine the methods used in publishing the data obtained in
other studies and publish some tables in which the Newburgh-Kingston data
were presented in the form used in these other studies. Owing to this
omission, they prevented comparisons being made with the results
published in the other studies considered in the monograph by: (a) not
disclosing any caries rates for deciduous teeth except in their 1951
report, (b) confining the rate "DMF teeth per 100 children" in
1953-54 to those aged six, seven, eight, nine and ten years (Ast et
a1.,1956); (c) combining the 1954-55 caries data into four groups
children aged six to nine years, ten to twelve years, thirteen to
fourteen years, and sixteen years of age (Ast a a1.,1956). In the other
main studies, although the DMF rates were shown per child or per 100
children, either clinical examinations only were used, or the data were
reported for individual yearly ages or for age ranges which were
different from those used by Ast et
al. Thus, comparison of these rates with those published from the
Newburgh study cannot be made.
(95) "What is significant and
had escaped Sutton is the fact that the percentage differences in
Newburgh and Kingston were almost the same for both methods used."
Comment.
Dr Ast, no doubt, did not mean to suggest that the results were almost
the same in the test and the control cities, but intended to refer to the
percentage differences (in caries rates) between Newburgh and Kingston.
It is surprising that Dr Dunning
should have published this remark of Dr Ast, for a paper which he wrote
almost ten years earlier (Dunning, 1950) showed that he realized the
inadequacy of results stated merely as percentage reductions. In the
summary of that paper he pointed out that "Interpretative and other
examining errors in DMF studies may be large, easily exceeding 100 per
cent differences between samples." He said also that:
"Illustrations of actual data
indicate that the standard deviations of observations about the means
(averages) in DMF studies are large even where examining errors are
reduced to a minimum." Dr Dunning then said that: "These two
sources of variability imply that human DMF studies should be subjected
to close scrutiny as to the validity of the data and statistical significance
tests applied and reported wherever possible. Mere statements that
"caries was reduced by x per cent" are not sufficient."
It can be seen that it is precisely
this method of presenting data, that Dr Dunning criticized in 1950, which
was used by Ast et al. to
report the results from the Newburgh trial: "Mere statements that
"caries was reduced by x per cent" (differences between the
test and the control cities) without "statistical significance tests
applied and reported."
(96) "Another criticism made is
that baseline data were collected in Kingston a year after the Newburgh
survey. I can't believe Sutton really believes this to be valid
criticism. He must be, or should be aware of the fact that caries is not
an acute disease of short duration, but a slowly developing one
..."[end of published quotation].
Comment.
Dr Ast is wrong in his assumption - it certainly is considered to be
valid criticism to point out that the initial examination was not made in
the control city until after the fluoridation of the test one. By writing
about the obvious fact "that caries is not an acute disease of short
duration, but a slowly developing one" Dr Ast avoids the significant
point: that he and his co-workers assumed that the caries rates in the
children in the control city would be similar to those in the test one,
and that they omitted, prior to starting the experiment, to test this
vital matter.
(97) "The baseline data in
Newburgh and Kingston based on the examination of all the school children
age six to 12 in both cities were almost identical. All of the
examinations were made by the one examiner. Could Sutton really believe
that the DMF rate of 20.8 for Kingston, and the 21.0 for Newburgh could
have been significantly different if both examinations were made exactly
at the same time?..." [end of published quotation]. "... this
type of criticism questions not the research but the professional acumen
of the critic."
Comment.
Dr Ast and his co-workers were fortunate that they were able to present
figures for caries rates which were comparable, although the fact should
not be forgotten that they improved the comparability between the initial
caries rates in the test and the control cities by combining the data
from children of different ages.
The workers who conducted the Evanston
study made the same assumption and failed to examine the children in the
control city until after the fluoridation of the test one (Blayney and
Tucker, 1948; p. 153). They were not as fortunate as were Ast et al., for they found "...a
lower caries rate for school children of the control area" (Hill et al., 1951). In the younger
children, there were gross differences between the initial caries attack
rates in Evanston and its control city. The same omission was made in the
trial in Hastings, New Zealand. As a result, the control was abandoned,
for its caries rates were lower than in Hastings (Ludwig, 1958).
DR J. R. BLAYNEY
Dr Dunning then said that "J.R.
Blayney, Director of the Evanston Dental Caries Study, comments thus
(Blayney to Adamson, November 23,1959)". Dr Blayney is reported to
have written (98-100):
(98) "Dr Sutton ....states,
"the arbitrary selection of the data which is then termed
"representative", instead of making the ultimate findings to be
considered valid and reliable, would render a report based on this
selective data unfit for serious consideration."
Comment.
This "quotation" is inaccurate. Dr Blayney has omitted the
words "a section of and refers to "selective data" instead
of to "selected data" . The original paragraph was:
"However, the process which they described - the arbitrary selection
of a section of the data, which is then termed "representative"
- instead of making "the ultimate findings to be considered valid
and reliable", would render a report based on this selected data unfit
for serious consideration."
(99) "We feel that this type of
criticism is unworthy of the scientific nature and dignity of the
University of Melbourne and would tend to imply that the rather
reasonable separation of white and Negro, public and parochial children,
for the purpose of comparing like with like, is an "arbitrary
selection" making the "data unfit for serious
consideration" and that the entire report hinges only on this
pre-selected data. "
Comment.
This comment by Dr Blayney to the President of the Australian Dental
Association is misleading. The statement by Hill et al. (1950), which was quoted on pages 151 and 152 and to
which the comment made by the author of the monograph refers, made no
mention of the "separation of white and Negro, public and parochial
school children", but instead, stated the intention of including
"... only those groups of children which are representative of the
population, with respect to dental caries experience",
Hill and Blayney originally did not
intend to separate the children into racial and school groups. It was not
until their 1951 report that mention was made that they contemplated such
an action, that is, not until a year after they published the statement
mentioned above. They decided to separate the
Evanston data into racial and school groups when they found that the
initial examinations "... indicated a lower caries rate for school
children of the control area" (Hill et al., 1951). They have not explained why it was necessary
to exclude from the main body of white children those who happened to
attend the parochial school, rather than the public one.
As they consider that Negroes have
less dental caries than white children it is, of course, reasonable to
consider the data of white children separately from those of Negro
children. However, Hill et al.,
first included the data of Negro and parochial school children (with
those of the white children attending public schools), then excluded
these (Negro and parochial school) data for several years, and then, despite
their statement that such a process was necessary, reversed their policy
and included these data with those of the white children attending public
schools. By this reversal of policy they were able to present initial
caries rates for the test city which were more comparable to those in the
control city than would have been the case if they had not disregarded
their previously-stated policy of comparing
"like with like". This cannot be considered to be a reasonable
course of action.
(100) "We have gathered no
secret or concealed data" ...[end of published quotation].
Comment. This assertion by Dr Blayney should be considered in the
light of the numerous instances, in his study, in which relevant data
were not published, in some cases even for as long as twelve years after
they were obtained.
The failure of Dr Blayney and his
co-workers to publish these relevant data has, without question,
concealed them from readers of their reports.
Dr Dunning quoted two further
paragraphs from Dr Blayney's letter. These were printed in the "Book
Review" published in the Australian Dental Journal in the February,
1960, issue.
DR J.M. DUNNING
The criticisms made by Dr Dunning
himself will not be considered, for his attitude to the monograph and the
lack of care in the preparation of his critique are evident from even one
example:
He stated that "In discussing
requirements for a control, Sutton adopts the position that the control
city should be "comparable in all respects" to that where
fluoride is being added." That phrase was not used by the author of
the monograph, but was quoted by him from two sources (pp. 141, 178,
179,190). His, considerably different, views on this matter were stated
on pages 190 and 193.
Therefore, by attributing to the
author an opinion which he did not express, and that he actually
criticized (p. 190), and by omitting the different opinion that the
author did express, Dr Dunning misleads his readers.
Furthermore, the fact that Dr Dunning
has elected to publish these extracts from letters written by authors of
fluoridation trials, indicates either that he has chosen to ignore or has
failed to detect errors in them which should be obvious to a careful
investigator.
In 1984, twenty-four years later, Dr
Dunning was still criticizing papers which questioned fluoridation. He
continued his former technique of misleading his readers by inventing
false statements, attributing them to the author of the article he was
criticizing, then disputing his own false statements. He stated that
Colquhoun (1984):
"... mentions an increase in
periodontal disease as if it might have been caused by
fluoridation."
In fact, Colquhoun (1984) stated
that: "... water fluoridation does not affect" periodontal
disease.
Dr Dunning also wrote that:
"Colquhoun continues to quote
Sutton on the subject of defects in early studies of fluoridation,
stating that he (Colquhoun) has seen no convincing refutation of this. I
offer him my article, "Biased Criticism of Fluoridation" in
which I quote the views of several of the leading fluoride researchers of
the day. The studies Sutton criticizes most harshly have survived as
pioneer efforts and been confirmed not only for their conclusions but for
their methodology."
This was the paper in Nutrition
Reviews, mentioned above, which has remained unchallenged in print until
now, years after it was written, because of the difficulty in having
accepted for publication any material which questions fluoridation.
It is interesting that Dr Dunning
(1984), after so many years, can call the authors of the original
studies:
"... the leading fluoride
researchers of the day".
and say that their methodology had
been accepted, when he himself (Dunning, 1950) condemned the method they
used of expressing caries changes as percentages without the use of
statistical tests.
That Dr Dunning now accepts their
methods, such as that used in the Evanston study which led to the authors
admitting that they had made gross errors in stating the number of
children seen during one examination, one of which was a discrepancy of
more than 1000 children shows that he should be included with those
described by Professor John Polya (1964) as:
"... unreliable witnesses before
a jury either of scientists or of lay common sense."
It is clear that Dr Dunning's
criticisms can be disregarded. He is one of those critics whose intense
pro-fluoridation opinions have made them muddled thinkers, and he is one
who intentionally manufactures incorrect statements about those he
criticizes to try to attack work which he cannot find grounds to fault by
legitimate means.
ADDITIONAL OBSERVATIONS ON THE EVANSTON, GRAND RAPIDS AND
NEWBURGH TRIALS
1. Gross numerical errors in statements of the number of
children examined.
The Evanston Trial
These comments on the Evanston trial
were published in 1980 in the present author's book Fluoridation
Scientific Criticisms and Fluoride Dangers. It was stated:
"Additional Errors in the
Evanston Trial Data.
In January, 1967, which was the
twentieth anniversary of the commencement of the Evanston Trial, an
entire special issue of the Journal of the American Dental Association
was devoted to a report on that study (Blayney and Hill, 1967). In this,
the original tables, complete with their gross numerical errors, were
reproduced, despite the fact that these [errors] had been pointed out
eight years earlier (Sutton, 1959) and some of them had been acknowledged
by the authors (Sutton, 1960). In addition, several faulty tables were
published for the first time.
The tables [in this issue of the J.
Amer. Dent. Ass.] then showed three different statements regarding the
number of children aged 6-8 years who were examined in Evanston during
the 1946 examination:
(i) 1991 children - see Tables 10,
11,30,40 and 47.
(ii) 1985 children - see Tables 7,8,16,18,21 and 32.
(iii) 1754 children - see Tables 24 and 25.
There were also no fewer than six
different statements in that article of the number of children aged 12-14
years examined in Evanston in 1946:
(i)
1703 children - see Tables 15 and 32.
(ii) 1702 children - see Table 47.
(iii) 1701 children - see Tables 11,30,41,44 and 45.
(iv) 1697 children - see Tables 7,9,12,13,17,19,22 and 31.
(v)
1556 children - see Table 26.
(vi) 1146 children - see Table 46.
Between the sum of the two highest
statements of the number of children examined in Evanston in 1946, and
the sum of the two lowest statements of children examined in the same
year in the same study in the same city, there is a difference of 794
children (1991 + 1703 - 1754 - 1146 = 794).
The number of children stated to have
been examined in Evanston is even more divergent in the original papers
than in this special article. Blayney and Tucker (1948) and Hill et al. (1950) both gave a figure
of 4375 children, compared with the number of 3310 in Hill et al. (1957b), a difference of
1065 children.
It was these differences which the
medical journalist Anne-Lise Gotzsche, in a letter to the Lancet in 1975,
said that she had showed to workers in other fields, and that they had
"simply laughed" at the statistics (see Fig. 5, p. 167).
In that book (Sutton, 1980) -
prepared as a submission to the Committee of Inquiry into the
Fluoridation of Victorian Water Supplies (1980) - it was stated (p. 203):
"These errors were mentioned [by
the present author] 12 years ago to the Tasmanian Royal Commission on Fluoridation.
Since that time I have not heard of any mention of them or of a criticism
having been made of the numerical data published in that report."
It appears that, in the manner common
in fluoridation trials, those erroneous tables have been accepted at
their face value, without investigation.
More than thirty years ago it was
pointed out (Sutton and Amies, 1958b) that:
'This uncritical attitude to these
studies is rife." "Also it has been assumed that associations
and individuals that ... accepted the responsibility of publicly
advocating fluoridation, have undertaken independent examinations of the
data, and not merely repeated the opinions of others."
This situation was referred to by
Professor John Polya (1964) in his book Are We Safe? He wrote:
"It is immaterial that other
evidence in favour of fluoridation is not always false; the point is that
persons, bodies and arguments that knowingly or in simplicity acquiesce
in one blatant falsehood are unreliable witnesses before a jury either of
scientists or of lay common sense."
He continued:
"The scandal created by the
exposure of this absurdity resulted in the admission that the first
figure (4,375) was correct. In defence of the other claims it was
explained that "out of range" children were eventually excluded
from the survey, but then further critical check revealed more numerical
inaccuracies, not to speak of the magnitude of a correction exceeding
1,000. In better examples of scientific work the author sticks to his
experimental group; discarding on the scale quoted strongly suggests that
the experiment had to be altered to fit pre-conceived results. This is
one of the common consequences of working without control of observer
bias."
It is pertinent to point out that, in
the Foreword to that article in the special edition of the Journal of the
American Dental Association, in January 1967, Dr F.A. Arnold, Jr., the
Assistant Surgeon General, Chief Dental Officer, U.S. Public Health
Service (and formerly the chief experimenter in the study in Grand Rapids)
stated:
"Here, in a single report, are
data on the effect of water fluoridation on dental caries so completely
documented that the article is virtually a text book for use in further
research. It is an important scientific contribution towards the betterment
of the dental health of our nation. It is a classic in this field."
It is indeed a classic - a
first-class example of the errors, omissions and misstatements which
abound in the reports of these fluoridation trials.
2. False information in the Abstracts of papers
The abstracts of reports on
fluoridation trials are unusually important, for it is likely that lay
people, and politicians in particular, will confine their reading of the
report to the Abstract, assuming that it accurately reflects the findings,
and will base their opinions and actions on its statements.
The Grand Rapids Trial. The final report of the Grand Rapids
study was published in 1962. Reading the Abstract which preceded the body
of the article it would seem that, at last, the authors (Arnold et al., 1962) had come to realize
the necessity for comparing the results from the test city with those
from the control one for they stated that the results had been
"...compared with the caries attack rates in the control group of
children in Muskegon, Mich." This claim was not made in the body of
the article, which included the statement that: "... fluorides were
introduced to this [Muskegon] water supply in July, 1951" Therefore
at that time Muskegon ceased to be a control city, some eleven years
before this final report (Arnold et
al., 1962) from Grand Rapids.
How then, in 1962, could the final
result from the test city be compared with data from a non-existent
control one?
The claim of Arnold et al. (1962) that they compared
the Grand Rapids caries rates with those in the "control group of
children in Muskegon, Mich." is shown to be false by their statement
that: "...in subsequent [after 1954] analyses of Grand Rapids data,
comparison has been made with the original Grand Rapids findings and with
those for Aurora."
This is confirmed by the statement in
the Abstract that:
"Caries attack rates were
lowered by 57 per cent in children 12 to 14 years old in 1959." This
figure of 57 per cent is obtained by averaging the figures of 57.0, 63.2
and 50.8 per cent for the ages of 12, 13 and 14 years shown in their
Table 2 to be the "per cent reduction in DMF teeth (19441959)"
in Grand Rapids (not between Grand Rapids and its control city of
Muskegon).
The Newburgh Study. Similar mis-information regarding comparisons being made
between test and control cities was published in the same year (1962) by
Dr David Ast, the senior author of the Newburgh study. In the Abstract of
that paper (Ast and Fitzgerald, 1962) he wrote:
"Among children 12 to 14 years
old in the four study areas, reductions in the DMF rates as compared to
the rates in control cities ranged from 48 to 71 per cent."
Table 2 is the only one in that paper
showing DMF rates for children aged 12-14 years (in one case 13-14
years). In the first two studies listed, Grand Rapids and Evanston, no
reference is made to a control, the "reduction" in Evanston,
shown as 48.4 per cent, is obviously the 48 per cent mentioned in the
Abstract. This "difference" is between the rates in Evanston in
1946 and 1959, not between Evanston and a control, as stated in the
Abstract. The Grand Rapids rates are also shown between that city in
1944-45 and 1959, no control data being used. Indeed Ast and Fitzgerald
stated in the main text:
"In the Grand Rapids and
Evanston studies the control cities were lost before the study was
completed, so that the current data have been compared with the base line
data."
Not with control cities, as they
stated in their Abstract.
There should not have been any
confusion regarding the use of the term "control", for the
co-author of that paper, Bernadette Fitzgerald, was described as the
"senior biostatistician, division of special health services, New
York State Department of Health." Therefore the authors' incorrect
statement that they compared the caries rates "in the four study
areas" with rates in control cities is unlikely to have been made
inadvertently.
3. Continuing publication of false statements.
It has just been shown that Dr Ast
(the senior author of the Newburgh study) and Dr Arnold (the senior
author of the Grand Rapids study) continued to disseminate false
statements regarding their studies many years after those ten-year
studies were concluded, Also, the arrogance of Drs Blayney and Hill (the
authors of the Evanston study) in publishing an article in 1967, which
repeated, in a special issue of the Journal of the American Dental
Association, figures which they had acknowledged seven years earlier were
faulty (Sutton, 1960), indicates the reckless disdain of all those
authors for the truth, and for the members of the scientific community
(which normally trusts statements made in established journals by senior
scientists, for it is not used to being misled by such readily-verified
deceptions).
Their false statements do not
engender confidence in the reliability of the data published and the
statements made by those senior scientists in their original reports of
what are still regarded by fluoridation advocates as three of the four
main fluoridation studies on which the case for fluoridation mainly
relies - those in Newburgh, Grand Rapids and Evanston in U.S.A.
Commenting on the Grand Rapids study,
Ziegelbecker (1983) pointed out that the experimenters had examined
"all" children from 79 schools in Grand Rapids at the
commencement of the trial, but that:
"After 5 years in 1949 they
selected children at only 25 schools in Grand Rapids for their
investigation and observed children at the same time at all schools in
Muskegon (the control city)."
For instance, the number of children
aged 12 to 16 years who were examined in Grand Rapids at the commencement
of the trial was 7,661, but only 1,031 were examined in 1959 (Arnold et al., 1962).
In 1988, Colquhoun stated:
"In the control city of Muskegon
all children were examined throughout the period. From the year-by-year
figures for six-year-olds which were published three years later in 1953,
it is revealed that an impossible 70.75% reduction was recorded in the
first year of the trial (Arnold et
aL,1953) and that there was then an increase and no overall reduction
in the following years. Examination of similar data for other age groups
shows that the sample of 25 schools could not have been representative of
the population being studied."
He pointed out that:
"The reported DMF of several of
the age groups in this sample, approximately one year after the initial
examinations, was lower than that of the same children when they were a
year younger."
He concluded:
"Fluoridated water cannot turn
decayed, missing or filled teeth into sound ones. It follows that the
caries experience of the children had not been reduced as claimed. The
large recorded reductions, which were mostly in the first year only, were
a result of selection of data."
4. Fictional results?
In 1954 De Stefano reported the
findings of professional statisticians regarding the Grand Rapids study.
They raised the question whether "... the reported results are
merely the fiction of a biased sample."
Ziegelbecker (1983) also, studied
this situation. He stated:
"We must conclude from this result
that the sample in Grand Rapids was not representative for all children
and with respect to the basic examination. In the following years from
1946 to 1949 (and later to 1954) the 25 schools in the sample were the
same each year and we see that the caries experience in the sample was
not reduced by fluoride in 1946-1949.
If we accept that the sample was
representative for the children, aged 6, in the 25 schools in those years
then we must conclude that fluoride in the drinking water had not reduced
the dental caries experience of children, aged 6, in Grand Rapids in the
years before the US Public Health Service released the policy statement
[endorsing fluoridation] to the American Dental Association."
He concluded:
"We must conclude from these
results that a fluoride content of 1 ppm in the public water supply does
not reduce dental caries experience."
Colquhoun stated in 1988:
"In their final study in Grand
Rapids, published in 1962 after 15 years of fluoridation, American health
officials [including the director of the U.S. National Institute of
Dental Research, Dr F.A. Arnold, Jr.] wrote: "... no such dramatic
and persistent inhibition of caries in large population groups had ever
been demonstrated by any other means than fluoridation of a domestic
water supply."
Colquhoun commented:
'That statement, which could be
described as the dogma of fluoridation, is now considered by an
increasing number of critics to be unscientific and untrue."
In view of the disclosure of the
types of error which have just been mentioned, such a grandiose claim,
although it was widely accepted at the time, can no longer be considered
to be true.
More than thirty years ago Sutton and
Amies (1958a) commented on this sudden initial decrease in caries
reported from Grand Rapids (and from other studies considered). It was
stated that the results reported were not those which would be expected
if the hypothesis was correct that fluoride "strengthens"
developing teeth and makes them more resistant to attack by caries.
Despite the fact that the results published from fluoridation studies do
not support this hypothesis, it is still mentioned. For instance, the ten
members of the task group which in 1984 wrote the latest WHO book on this
subject: Environmental Health Criteria 36. Fluorine and Fluorides,
referred to the importance of "lifelong consumption" of
fluoridated water.
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