In sharp contrast to reports from child protective services agencies, which show a halving of physical abuse cases, an analysis of hospital records in the US by Yale researchers shows cases of serious physical abuse injuries in children rose slightly in the 12 years up to 2009. The researchers say the big difference in the results highlights the challenge of relying on one source of information to keep an eye on serious problems.

Yale University released details of the study for Monday. A full report is due to be published in the November issue of Pediatrics.

Study authors John M. Leventhal, professor of pediatrics and nursing, and Julie R Gaither, a graduate student in the School of Public Health at Yale, found that serious cases of physical abuse in children in the United States rose by 5% between 1997 and 2009. Serious physical abuse includes head injuries, burns and fractures.

In contrast to this, for the same period, data reported by US child protective services agencies, show a 55% fall in physical abuse cases.

Yale University says the study raises concerns that the child protective services figures may be due to changes in reporting practices rather than reflecting a true reduction in child abuse cases.

Another possible explanation for the stark contrast, is the child protective agencies’ data included all cases of physical abuse, regardless of severity. The Yale researchers considered only serious cases.

Leventhal says their results “highlight the challenges of helping parents do better by their children and the importance of effective prevention programs to reduce serious abusive injuries in young children”.

The contrast between the two sets of data shows the difficulty of using a single source of information to follow an issue as complex as child abuse, adds Leventhal, who is also director of the Child Abuse Programs at Yale-New Haven Children’s Hospital.

For their study, he and Gaither used data from KID (the Kids’ Inpatient Database), which samples discharge records from US hospitals.

They looked for cases of serious injury linked to child abuse from 1997 to 2009. KID stores injuries as codes. For instance there are different codes for head injuries, fractures, burns, and abdominal injuries.

The database also holds demographic information, so for each case, the researchers were able to extract the child’s age, gender, race, and health insurance information. They were also able to see how long the child was in hospital for, and if he or she died while in hospital.

Their analysis shows that in the 12 years to 2009, there was a 4.9% rise in the number of children hospitalized as a result of serious abuse-related physical injuries.

The Child Abuse Funds in Yale’s Department of Pediatrics financed the study.

Written by Catharine Paddock PhD