Much stronger evidence and standardized protocols are urgently needed to correctly identify suspicious sudden infant deaths, concludes a review of the available research in Archives of Disease in Childhood.

And where cases are tried in court, the proceedings would be fairer and less contentious if the recent reforms applied to the use of expert witnesses in civil cases were also extended to criminal courts, suggest the authors.

It is impossible to be certain, but an estimated one in 10 of the current annual total of sudden unexplained deaths among infants under the age of 12 months is actually a case of undetected homicide, ranging from murder to neglect. This figure is equivalent to between 30 and 40 such cases a year in England and Wales.

The number of natural infant deaths has steadily fallen to around 300 a year, of which 180 are registered as cot death or SIDS, but the number of suspected covert homicides is thought to have remained constant.

The authors, from the research charity, the Foundation for the Study of Infant Deaths, base their calculations on figures from the national Confidential Enquiry into Stillbirths and Deaths in Infancy for to .

They take in the main research published to date, but point out that some of the criteria that have been used to detect covert homicides are not sufficiently robust and distinctive to allow definitive conclusions to be drawn. This includes the probability of murder where there has been more than one sudden unexplained infant death in the same family.

Repeat deaths are always a cause for concern, say the authors, but a thorough search for known and unrecognized familial disorders must be undertaken before any verdict is reached as to the cause of death. "Each family has its own unique blend of genetic and environmental factors that determines its susceptibility," they write.

They describe the current understanding of covert homicide in infancy as "very inadequate." The rates, patterns, clinical features, pathology, as well as the profiles and motivations of the perpetrators all need to be urgently researched, they say.

"The present lack of an adequate evidence base is particularly dangerous in an area where wrong diagnosis in either direction can lead to disaster. If covert homicide is missed, another baby may be killed, while false accusation may lead to wrongful imprisonment and destruction of a family," they conclude.

In line with the Foundation for the Study of Infant Deaths as well as the American Academy of Pediatrics, they recommend that all investigations should include: A visit to the home by a pediatrician soon after the death to talk with the parents and inspect the scene A post-mortem examination carried out by a specialist pediatric pathologist, following set procedures, and including tests for familial disorders A discussion of the case among all the professionals involved, including the family doctor and health visitor

Source: British Medical Journal