Predictors of increasing injury severity across suspected recurrent episodes of non-accidental trauma: a retrospective cohort study

Many children who are victims of NAT may not experience abuse as a one-time event, but rather as a recurrence that is part of the high-risk environment in which they live. This is the first study, to our knowledge, to use administrative claims data from a pediatric Medicaid accountable care organization to identify risk factors for escalating severity of injury in children with multiple events of suspected NAT. In this study, factors predictive of an increased risk for more severe subsequent episodes of suspected NAT include living in a rural area, having an open wound and having a superficial injury. Conversely, having more injuries is predictive of a decreased risk for a subsequent episode of suspected NAT of increasing severity.

Population-based studies and analyses of large datasets are becoming increasingly important in studying recurrent NAT. Friedlaender et al. analyzed system-level Medicaid claims data to characterize the health service use patterns of maltreated children in the year before their first reported episode of maltreatment [16]. The authors demonstrated that victims of maltreatment changed ambulatory care providers with greater frequency than those children who were not abused. The study design, however, did not allow for the study of recurrence of abuse nor identification of specific patterns or types of injuries that place a child at increased risk for recurrent maltreatment. Schmitt et al. studied a population of abused children who were returned to the home in which the abuse occurred and found that these children had a higher risk of a fatal recurrent episode of 5–10 % [6]. Similarly, Putnam-Hornstein et al. prospectively studied a population of over four million children following a nonfatal allegation of maltreatment [7]. Findings from this study indicate that after adjusting for risk factors at birth, children with a prior allegation of maltreatment died from intentional injuries at a rate that was 5.9 times greater than unreported children (95 % CI [4.39, 7.81]). In a previous analysis, we demonstrated that child victims of recurrent abuse had significantly higher mortality rates compared to victims of a single episode of abuse (24.5 % vs. 9.9 %; p?=?.002) [8]. We also have previously reported on risk factors associated for recurrent injury in victims of suspected NAT, including young age of the victim (30 months) and initial presentation with “minor” injuries, such as dislocations, open wounds and superficial cutaneous injuries [9]. Our present study adds to the existing literature by identifying factors associated with children experiencing recurrent episodes of NAT of increasing severity. This type of data may help health care providers to develop screening protocols to identify children at the highest risk for subsequent serious injury at their initial episode.

Our findings highlight a potential bias in the identification and diagnosis of injury by the healthcare provider, or in the subsequent child protective services response to children who present with “minor”, or less numerous injuries. It seems likely that children with “minor” or less numerous injuries are either not reported to child protective services by the healthcare provider or not removed from the unsafe environment despite a report being made, with either situation leading to subsequent events. Sheets et al. report that nearly one in three children evaluated for abuse were seen previously with a sentinel injury, the vast majority of which were simply bruises [17]. Our data demonstrate that not only are these children more likely to experience subsequent events, but identifies specific risk factors that are predictive of increasing severity across recurrent events. Likewise, our finding that children living in rural areas are at increased risk for escalating severity raises the idea that resource scarcity may be a concern, either with access to medical expertise to identify injuries or with the ability of the child welfare system to respond appropriately to concerns.

There are several limitations related to using system-level administrative claims data in this study. First, approximately 35 % of patients had at least one break in Medicaid enrollment during the study period with the potential that recurrent events could have occurred during the time of non-enrollment; therefore our data may be an underestimate of recurrent events. However, in a sensitivity analysis excluding children with discontinuous enrollment during the study period, the findings were similar, though the number of injuries and having a superficial injury no longer reached statistical significance in this subgroup. Second, as with any study utilizing claims data, we are limited in the sensitivity and specificity of the ICD-9 coding practices used to identify key variables. Specifically, ICD-9 coding from an admission may underestimate the prevalence of abusive injuries as physicians may be reluctant to assign a diagnosis of NAT without confirmation of the mechanism as child abuse from a multi-disciplinary investigation that is usually not complete until after discharge. Third, administrative datasets provide limited data on covariates of interest including race, parental characteristics, and SES characteristics. Lastly, this study lacked information on children removed from the home after suspected NAT events. Most children covered by PFK who go into child protective services custody are moved to fee-for-service Medicaid and thus no longer covered by PFK, though this varies by county in Ohio. Therefore, we were unable to follow the majority of patients who might have been placed in out of home care. Medicaid Analytic Extract (MAX) files might be useful to track these patients, in that Medicaid IDs could be used to follow children from PFK into fee-for-service Medicaid. However, we did not have access to this data for this study. The above limitations were unavoidable; however they likely resulted in under-identification of suspected NAT events with minimization rather than exaggeration of our findings. Although the last noted limitation could have biased our findings towards the identification of characteristics prevalent in children not removed from the home after suspected NAT, we were able to follow the majority of children who experienced severe events for more than 1 year after such an event