Heptonstall BMJ Response to Why can't the Daily Mail eat humble pie over MMR

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http://bmj.bmjjournals.com/cgi/eletters?lookup=by_date & days=21#121551

RAPID RESPONSE to BMJ's - Why can't the Daily Mail eat humble pie over MMR?

Humble pie? 19 November 2005

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P Heptonstall,

Director of the Morley Acupuncture Clinic

Leeds LS27 8EG

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Re: Humble pie?

Sir/Madam

I am grateful to Fitzpatrick for alerting us to the Cochrane review

of Demicheli, Jefferson et al into MMR and autism in his BMJ article “Why

can't the Daily Mail eat humble pie over MMR?”; I say that tongue in cheek

as I note that Dr. Fitzpatrick uses the Cochrane review to attack

for writing an article he terms a “symbol of the woe-ful role of

the media in the course of the MMR controversy”, and to claim that “The

recent publication of a Cochrane systematic review concluding that there is

" no credible evidence " of a link between the measles, mumps, and rubella

(MMR) vaccine and either inflammatory bowel disease or autism provoked

demands that the British tabloid newspaper the Daily Mail apologise for its

role in promoting the MMR-autism scare“ as it is not clear whether Dr

Fitzpatrick actually read the Cochrane review since it does not appear to

evidence his claims nor to have “provoked demands” Fitzpatrick speaks of.

The Cochrane review is extraordinary in that there are certainly statements

in that paper which, as Fitzpatrick argues, might lead readers to believe

that the “MMR causes autism” debate can finally be laid to rest and that

MMR is basically a safe intervention; I refer to the authors’ “No credible

evidence of an involvement of MMR with either autism or Crohn’s disease was

found”….”but the impact of mass immunisation on the elimination of the

diseases has been demonstrated worldwide”…”the safety record of MMR is

possibly best attested by its almost universal use”…”given the existence of

documented elimination of targeted diseases in large population by means of

mass immunisation campaigns however we have no reason to doubt the

effectiveness of MMR” yet the review does not appear to identify any

concrete scientific proof for those statements.

The objectives of the review are clearly stated to be “To review the

existing evidence on the absolute effectiveness of the MMR vaccine in

children (by the effect of the vaccine on the incidence of clinical cases

of measles, mumps and rubella). To assess in children worldwide occurrence

of adverse events including those that are common, rare, short and long

term, following exposure to MMR”. The team searched 5000 articles and pared

them down according to their own criteria until there were only 31 studies

that met the criteria for complete analysis – included in the ‘rejected’

4969 studies were all those attributed to Wakefield et al – therefore his

evidence of alleged MMR-induced IBDs and papers of Vijendra Singh et al

with powerful evidence of alleged measles virus (and later measles vaccine

virus) induced autism. Rejection from the final 31 had 4969 articles

discarded by the team’s specific criteria; of course one cannot claim that

the 4696 studies were invalidated by rejection, therefore the team cannot

claim for example that evidence for IBD/Crohn’s- induced colitis does not

exist as they ignored specific studies making that claim.

The findings of the Cochrane review are therefore founded on careful

analysis of the 31 studies that met criteria for study; only they provide

evidence for conclusions drawn by the team about their objectives on

“absolute effectiveness” and “worldwide occurrence of adverse events” for MMR.

I was therefore surprised, on analysing this paper for some considerable

time, that it appears to almost exclusively project the inadequacies of the

31 studies and not their inherent ability to prove or evidence the

objectives set by the authors! In fact the authors make it perfectly clear

that none of the 31 studies can be safely relied upon to evidence their

objectives. Perhaps I can show this most readily by referring readers to a

simple statistical representation derived from the authors’ critical

comments on the value of the 31 studies from which they attempt to attain

their objectives: -

1. NO study reported complete vaccine identification e.g. lot numbers,

adjuvants etc.

2. 39% failed to report ANY vaccine strains

3. 10% reported the strain for only one component of MMR

4. 84% failed to give complete information on schedule, doses, route of

administration

5. 58% failed to report definitions for all possible outcomes; 23% were

single event specific

6. 19% had NO definitions for safety outcome measurements beyond a

description of temperature range measurements; only 13% had ONE outcome

with description, and 16% more than one outcome with description

7. 48% of those monitoring temperature gave NO further description of

either numerical range or base reading

8. 19% reported NO participants missing for ADR monitoring; for 3% it was

NOT POSSIBLE to determine if participants were missing; 55% had ‘clearly

missing unintended event data’ of which 18% had under 10% missing from all

areas, 24% had between 11 and 20% missing, 47% had between 20 to 60%

missing from all areas and 12% the number of child subjects missing from

all areas COULD NOT BE DETERMINED.

9. 26% of the studies had inadequate explanation for missing data and for

12% no explanations were offered

10. 6% had discrepancies in reporting denominators

11. 3% excluded more than 33% of cases

12. 32% had insufficient information on study population and enrolment

13. 23% had population descriptions that raised doubts as to the

generalisability of their conclusions to other settings

14. 3% had uncertainty about power and generalisability of findings from

single case only design study

15. For 2 GPRD-based studies the precise nature of controlled unexposed

subjects to MMR their generalisability was IMPOSSIBLE to determine.

When one applies the above error-inducing factors to their respective

studies it is difficult to find one study devoid of sufficient error likely

to invalidate its findings. Is it any wonder the authors of the Cochrane

review also concluded “external validity of included studies was low”, that

”descriptions of the study populations, response rates (particularly in non

randomised studies), vaccine content and exposure (all important indicators

of generalisability) were poor and inconsistently reported”, and that there

was in addition “inadequate and inconsistent descriptions of reported

outcomes, limited observations periods (maximum 42 days) and selective

reporting of results”?

The question must be; why were supportive statements made by the authors

regarding safety and effectiveness of MMR which their detailed dismantling

of the validity of the 31 studies so obviously invalidate? One detects

almost ‘bipolar’ outpourings when comparing, for example, a statement like

“Existing evidence on safety and effectiveness of MMR vaccine supports

current policies of mass immunisation” with “the design and reporting of

safety outcomes in MMR vaccine studies, both pre- and post-marketing, need

to be improved and standardised definitions of adverse events should be

adopted”.

Perhaps the most damning statement for MMR vaccination the team makes

appears in their ‘Background’. They state “ despite its worldwide use, no

systematic reviews of the effectiveness and safety of MMR are available”.

Clearly, and despite the Cochrane review, the worlds’ children continue to

be afflicted by lack of a review which provides essential evidence of

effectiveness and safety of MMR vaccination..

Regards

H.

Competing interests: None declared

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Sheri Nakken, R.N., MA, Classical Homeopath

http://www.nccn.net/~wwithin/vaccine.htm