Research helping solve the mystery of cot death is still a long way off preventing the tragedy, warns a leading New Zealand child health expert.
Dr Ed Mitchell, Auckland University professor of child health research, said an American study that revealed a possible cause of the syndrome was"interesting and important".
The study showed sudden infant death syndrome victims had a brain abnormality which prevented the babies' brains realising their bodies did not have enough oxygen.
But Dr Mitchell said the work had identified only one genetic abnormality, when it was likely that multiple abnormalities led to Sids.
And he warned that a test for identifying vulnerable babies was a long way off.
"It's still a dream," Dr Mitchell said. "It doesn't help mothers avoid Sids."
Putting babies to sleep on their backs, avoiding bed-sharing and stopping mothers smoking during pregnancy remained the most important messages in avoiding cot death.
A new message was "sharing the parental bedroom".
Dr Mitchell said he and others had done research in New Zealand 10 years ago that showed babies under six months who slept in cots next to their parents' beds were less likely than other infants to die of Sids.
Since then, four studies around the world had reached the same conclusion - showing the risk dropped by a third to a half, although the reason was unknown.
"We don't know what the mechanism is, but it's very consistent," Dr Mitchell said.
The Ministry of Health is planning to promote children sleeping in their parents' bedroom for the first six months of their lives in a new campaign to cut the rate of Sids, which kills 50 babies a year in New Zealand.
The ministry's chief adviser of child health, Dr Pat Tuohy, said pamphlets would be sent to health practitioners to provide to parents in the next few weeks.
The Cot Death Association said it had known of the evidence for some time and would also update its recommendations.
