Incidence of serious injuries due to physical abuse in the United States: 1997 to 2009.

BACKGROUND AND OBJECTIVE Although US child protective services data showed a 55% decrease in the national incidence of substantiated physical abuse from 1992 to 2009, no study has tracked the occurrence of serious injuries due to physical abuse. This study examined changes in the incidence of serious injuries due to physical abuse in hospitalized children from 1997 to 2009. METHODS The Kids' Inpatient Database, a sample of discharges from hospitals in the United States, includes International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis and external cause of injury codes; it was prepared every 3 years from 1997 to 2009. Cases of serious physical abuse (eg, abusive head injury) were identified by using injury codes (800-959) and codes for abuse (995.50, 0.54, 0.55, and 0.59), selected assault codes (E960-966, 968), or perpetrator of abuse (E967). The weighted number of hospitalizations due to serious physical abuse was used to calculate the national incidence, and χ(2) for linear trend compared over time the incidence for children <18 years and <1 year of age. RESULTS The incidence per 100,000 children <18 years of age increased 4.9%: 6.1 (95% confidence interval = 5.4-6.8) for 1997, 6.0 (5.2-6.7) for 2000, 6.0 (5.3-6.7) for 2003, 6.1 (5.3-6.8) for 2006, and 6.4 (5.7-7.2) for 2009 (P < .01). The incidence for children <1 year of age increased 10.9% (P < .05). CONCLUSIONS Over 12 years, when substantiated physical abuse was declining, there was a small increase in the incidence of serious physical abuse in children <18 and <1 year of age.