Leader: Dissent must be aired

The controversy over the safety of the measles, mumps and rubella vaccine contains difficult lessons for everybody involved. It is important to learn them in a climate in which researchers are encouraged to look for new sources of funding while maintaining the credibility of their work.

The MMR researchers led by Andrew Wakefield made a number of mistakes. Perhaps the worst was their failure to appreciate the importance of taking money from one side in a legal dispute where substantial damages were at stake. Taking cash from a source such as this is inherently problematic, in a way that money from a charity or a research council is not, and requires special handling. The Royal Free Hospital medical school, where the work was done, is part of University College London, one of the world's biggest medical research centres. It should have a research office capable of seeing such problems coming. Ethics committees are concerned with the content of research, not its funding, and cannot be given this responsibility.

So far, it has been left to medical journals to police research via the declarations of interest authors have to disclose as part of the process of getting published. Their role has been a positive one, but by the time the paper has been written the damage has been done. Scrutiny that avoids problems in advance is preferable to a system that picks them up after the fact.

The MMR case is especially visible because it touches on child health and parental care. Newspapers reported Dr Wakefield's work prominently despite the fact that it was a minority view contested by many other experts.

Perhaps they could have been clearer about how controversial the issue was.

But science is decided on evidence, not a majority vote. For all the problems surrounding this research, unpopular opinions must still be heard.