You're sitting on a university's ethics panel. A proposed experiment into the neurobiology of social behaviour comes up for approval. Subjects' brains will be scanned while they perform a series of tasks. Some of the participants have a history of disturbed social behaviour; one task involves viewing violent images. On completion, participants are simply asked to leave the laboratory. Would you give the experiment a green light?

If you're not sure, don't worry: neither are many real ethical review boards. When Canadian researchers asked their country's boards to rule on the protocol described above, they found a startling lack of conformity. All the boards that responded seemed to use similar ethical norms when judging the project, but thirty rejected it, ten approved it with qualifications, and three waved it through unconditionally (J. de Champlain and J. Patenaude J. Med. Ethics 32, 530–534; 2006).

“Everyone knows institutional review boards make very different decisions,” says Joan Sieber, a psychologist at California State University, East Bay, who helps to train board members. She argues that it would be unrealistic to expect all boards to reach the same decision, but that the range of answers given shows that ethical norms are being applied in worryingly different ways. “This shows that something needs to be done.”

The Canadian study is the work of Johane de Champlain and Johane Patenaude from the University of Sherbrooke in Quebec. The pair say they wanted to examine the belief that “considerable divergence” exists between review boards. In their experiment, each board knew that the protocol it was viewing was fictional, but was told to handle the proposal as it would any other.

Some boards worried that the consent form did not tell participants they would be viewing violent images. Another complained that the rationale for the study — to gather neurobiological knowledge that would inform “the direction in which we wish to see society develop” — reminded them of the “atrocious eugenics movement in the late nineteenth century”. Two boards also noted that the rationale was not made clear in the consent forms.

Sieber says review boards need to be more rigorous in their risk assessments and decisions, and says they should call in outside experts where necessary. She adds, however, that a more common problem with institutional review boards is not a willingness to allow dubious studies, but an overly cautious approach that comes from ignorance of the experimental methods involved.