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LONDON - The British doctor who sparked a health scare by suggesting a childhood vaccine against measles, mumps and rubella is linked to autism faces a hearing starting today into charges of professional misconduct during his research.

The General Medical Council hearing, expected to last 15 weeks, centres on research published in the Lancet medical journal in 1998 in which Andrew Wakefield and colleagues posited a link between the MMR vaccine and autism.

The claim led to fierce worldwide debate among researchers and caused a decline in MMR vaccinations that health experts in Britain say has not yet recovered to the level seen before Wakefield's study.

Scientific evidence suggests that vaccines are not linked to autism but a vocal group of people remain unconvinced. Vaccine experts say parents often link vaccines with their children's symptoms because getting a shot can be upsetting, and children are vaccinated at an age when autism and related disorders are often first diagnosed.

The council will not look into the scientific claims but whether Wakefield and two colleagues - John Walker-Smith and Simon Murch - violated a number of ethical practices during the study involving young children.

"The panel will inquire into allegations of serious professional misconduct by Dr Wakefield, Professor Walker-Smith and Professor Murch, in relation to the conduct of a research study involving young children from 1996-1998," a spokesman said.

The council regulates doctors in Britain and could bar the three from practice. It said it would also look into charges Wakefield was involved in advising solicitors representing children claiming to have suffered harm due to the MMR vaccine. He faces a charge that he acted unethically by taking blood from children at a birthday party after offering them money and without proper ethical approval.

"My concern is that it's biologically plausible that the MMR vaccine causes or contributes to the disease in many children, and that nothing in the science so far dissuades me from the continued need to pursue that question," Wakefield said.

Before Wakefield's study, more than 90 per cent of children in Britain received the vaccination. After his warning that figure fell to around 80 per cent before rising to 85 per cent this year.