Last year, the study was retracted by the journal that first published it, the Lancet. Two of the researchers, Andrew Wakefield and John Walker-Smith, lost their licenses to practice medicine in the UK over accusations of misconduct in the running of the study. Wakefield subsequently worked for a time at the Thoughtful House Center for Children, in Austin, Texas.

A key claim in the original study was that 8 of the 12 children examined had started suffering developmental problems, including autism, just a few days after being given the MMR vaccine. but the children’s medical records (which were made public during the hearing into the researchers’ misconduct) show that this was true for just 2 of the 12 children (with information missing on another two). some children had symptoms before being given the MMR vaccine, and others developed them many months later.

Another of the study’s claims was that 11 of the 12 children had bowel inflammation. This inflammation, it was suggested, could be linked to both the MMR vaccine and developmental disorders such as autism. Original reports made by the hospital pathology service in the course of the study, however, said that just 3 of the 12 children had bowel inflammation. these reports were changed after being “reviewed” by the researchers.

Wakefield’s study suggested there was a new syndrome of regressive autism with bowel disease, and discussed the possibility that this might be linked to the MMR vaccine. it claimed that 6 of the 12 children had three key features of the new syndrome: bowel inflammation, regressive autism, and symptoms that developed days after having the MMR vaccine. the new investigation says that, according to medical records, none of the 12 children had all three features.

The investigation concludes that “no case was free of misreporting or alteration.” Dr. Fiona Godlee, BMJ Editor in Chief, says that there is “clear evidence of falsification of data.”

Good-quality research on the MMR vaccine shows no link with autism. the MMR vaccine can have side effects, but these are mild compared with the illnesses the vaccine prevents. In the early 1990s, more than 150 children died in the United States because of a measles outbreak among young children who hadn’t been vaccinated. Mumps can cause infertility in men, and rubella can cause serious birth defects if a woman is infected during pregnancy.

Some children who have the MMR vaccine get a high temperature, and a few children have seizures. but children usually recover quickly from these problems. There’s no evidence of long-term harm.

What you need to know. A study that’s often been often cited as showing a link between autism and the MMR vaccine has been labeled a fraud, with children’s medical records not supporting claims the researchers made about them. no good research has linked the MMR vaccine with autism. the vaccine is safe and effective, and the side effects are minor, especially when looked at alongside the potentially dangerous diseases the vaccine prevents.

—Philip Wilson, patient editor, BMJ Group

 ConsumerReportsHealth.org has partnered with the BMJ Group to monitor the latest medical research and assess the evidence to help you decide which news you should use.

For for information, take a look at our section on measles, mumps, and rubella prevention and read our previous coverage of the controversy.