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More than any other research, it was a study published in British medical journal the Lancet in 1998 that helped foster the persisting notion that childhood vaccines can cause autism. On Tuesday, that flawed study, led by gastroenterologist Dr. Andrew Wakefield, was officially retracted by the journal's editors — a serious slap and rare move in the world of medicine.

"It has become clear that several elements of the 1998 paper by Wakefield et al are incorrect, contrary to the findings of an earlier investigation," wrote the Lancet editors in a statement issued online.

Wakefield's work was the subject of what was almost certainly the longest medical-misconduct inquiry in British history, which concluded on Jan. 28. The U.K. General Medical Council, which licenses British doctors, found that Wakefield and two co-investigators had acted unethically and shown "callous disregard" for the 12 children in the study, which linked symptoms of autism and gastrointestinal trouble in eight of the children with their exposure to the MMR (measles, mumps and rubella) vaccine. Among other failures, Wakefield neglected to disclose that he was a paid adviser in legal cases by families suing vaccine manufacturers for harm to their children. It appears that he also handpicked the children for the study, rather than encountering them as consecutive patients at his clinic — another deception cited by the Lancet editors. And there were other lapses in the way Wakefield recruited research subjects — in one instance, paying children at his son's birthday party to give blood.

The three doctors cited by the council may be stripped of their right to practice medicine in Britain. But the findings of the inquiry come several years after the 1998 study had already been discredited and after 10 other co-authors had renounced its findings.

Now, with the formal retraction of Wakefield's paper, the question is whether the vaccine theory of autism may finally be put to rest. That seems unlikely. Since 1998, numerous studies have found no link between vaccines and autism, and yet parents' fears have endured. Indeed, vaccination rates in the U.K., which dropped after the publication of Wakefield's paper, never fully rebounded, and measles cases have taken off in Britain, leaping from 56 in 1998 to 1,370 by 2008. Cases have also risen in the U.S.

The vaccine fears persist in part because parents often notice the first autism symptoms around age 2, when many childhood vaccines are given. Most autism experts believe this is purely coincidental and that in many cases, parents have missed subtle signs of autism — such as a baby's failure to point and use gestures to communicate — that may have emerged before vaccination.

The vaccine theory also offers an appealingly simple explanation for a devastating and confusing ailment that seems to arrive like a thief in the night. It has been diagnosed with ever greater frequency, and the number of vaccines given in childhood has also grown in the past 20 years, making it easy target for blame. Experts believe that much of the increase in autism spectrum disorders owes to better detection, less stigma and broader definitions of autism, but this explanation fails to satisfy afflicted families.

Another reason that Wakefield's spurious conclusions had so much staying power was that his study focused on gastrointestinal symptoms in children with autism. Many autistic children have constipation, stomach pain and feeding issues that remain poorly understood. Says autism advocate and blogger Katie Wright, a Wakefield loyalist: "He was the first doctor to take this concern seriously and research why so many autistic children develop severe GI disease."

Wakefield, who is associated with the Thoughtful House Center for Children, an autism center in Austin, Texas, could not be reached for comment. He maintains a devoted circle of supporters, several of whom appeared with Wakefield on Jan. 28 in London, where the doctor traveled to hear the General Medical Council's findings.

For now, the standoff over the vaccine theory shows no signs of dissipating. Dr. Paul Offit, chief of infectious disease at the Children's Hospital of Philadelphia and author of Autism's False Prophets: Bad Science, Risky Medicine, and the Search for a Cure, says he has received hundreds of grateful letters from parents of children with autism thanking him for debunking the autism-vaccine connection. But he has also received death threats from families on the other side, who are a strong but committed minority. "It's easy to scare people, but it's extremely hard to un-scare them," says Offit.

• Claudia Wallis