The Accuracy of ICD Codes: Identifying Physical Abuse in 4 Children's Hospitals

Abstract

Objective To assess the accuracy of International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM), codes in identifying cases of child physical abuse in 4 children’s hospitals. Methods We included all children evaluated by a child abuse pediatrician (CAP) for suspicion of abuse at 4 children’s hospitals from January 1, 2007, to December 31, 2010. Subjects included both patients judged to have injuries from abuse and those judged to have injuries from accidents or to have medical problems. The ICD-9-CM codes entered in the hospital discharge database for each child were compared to the decisions made by the CAPs on the likelihood of abuse. Sensitivity and specificity were calculated. Medical records for discordant cases were abstracted and reviewed to assess factors contributing to coding discrepancies. Results Of 936 cases of suspected physical abuse, 65.8% occurred in children <1 year of age. CAPs rated 32.7% as abuse, 18.2% as unknown cause, and 49.1% as accident/medical cause. Sensitivity and specificity of ICD-9-CM codes for abuse were 73.5% (95% confidence interval 68.2, 78.4), and 92.4% (95% confidence interval 90.0, 94.0), respectively. Among hospitals, sensitivity ranged from 53.8% to 83.8% and specificity from 85.4% to 100%. Analysis of discordant cases revealed variations in coding practices and physicians’ notations among hospitals that contributed to differences in sensitivity and specificity of ICD-9-CM codes in child physical abuse. Conclusions Overall, the sensitivity and specificity of ICD-9-CM codes in identifying cases of child physical abuse were relatively low, suggesting both an under- and overcounting of abuse cases.

Hospital Variation in Cervical Spine Imaging of Young Children With Traumatic Brain Injury

“…26 A study of 4 children's hospitals demonstrated that abuse ICD-9-CM codes among children with TBI who underwent evaluation by a child abuse pediatrician had a sensitivity of 85.0% and specificity of 92.1% in correctly identifying abused children. 27 The use of ICD-9-CM codes to identify children with AHT at non-children's hospitals and hospitals without abuse specialists, however, has not been validated. Use of ICD-9-CM codes to calculate the incidence of AHT in children less than 1 year of age using nationally weighted administrative data of pediatric admissions (not limited to children's hospitals) produced comparable incidence estimates to those derived from a study using a prospective AHT surveillance strategy of all hospitals in North Carolina.…”

Potential Opportunities for Prevention or Earlier Diagnosis of Child Physical Abuse in the Inpatient Setting

“…We used a previously published coding scheme using validated abuse codes to identify children hospitalized for CPA. 2,20,21 In short, this scheme requires that 1 of the following 4 criteria be met: (1) ICD-9-CM codes for an injury (800-959) and abuse (995.50, 995.54, 995.55, 995.59, or E967), (2) ICD-9-CM codes for an injury and assault (E960, E966, E968), (3) ICD-9-CM codes for retinal hemorrhages (362.81) or anoxic brain injury (348.1) and abuse, or (4) any ICD-9-CM code for shaken infant syndrome (995.55). Exclusion criteria included late-onset injury effects, e-codes indicating that the injury occurred at a location not typical for abuse (eg, farms), or an abuse code at any previous encounter.…”

Prevalence of Abuse Among Young Children With Rib Fractures

“…5,22,29,30,32,34 Leventhal et al used ICD-9 E-codes to identify young children with abusive rib fractures, an ascertainment method shown to have high specificity for abuse. 22,35,36 Nonetheless, the abuse diagnosis criteria remain unclear with this method; thus, the study received a rating of 4.…”