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The study design was a case series: Andrew Wakefield and colleagues
did not state a hypothesis and case series studies are neither required
nor expected to state one. The purpose of a case series is to generate new
hypotheses about potential causation: it is not designed to investigate
possible causality. I am surprised and disappointed that the authors still
seem confused on this point.
The Lancet paper was hypothesis generating: an association between
the MMR vaccine and childhood autism was not "reported" in 'that paper'
published in the Lancet. In 'that paper' the Royal Free researchers had
"We did not prove an association between measles, mumps and rubella
vaccine and the syndrome described" ... (page 641, paragraph 2).
"Further investigations are needed to examine this syndrome and its
possible relation to the vaccine" (page 641, paragraph 5)".
 Wakefield AJ, Murch SH, Anthony A, Linnell J, Casson DM, Malik M,
et al. Ileal lymphoid nodular hyperplasia, non-specific colitis, and
pervasive developmental disorder in children [retracted]: Lancet 1998;