Racial and ethnic differences in pediatric unintentional injuries requiring hospitalization.

BACKGROUND/OBJECTIVE: This study aims to comprehensively examine racial and ethnic differences in pediatric unintentional injuries requiring hospitalization by age across injury mechanisms. STUDY DESIGN: This was a retrospective, nationally representative cross-sectional analysis of discharge data within the 2016 Kids' Inpatient Database for 98,611 children ≤19 years with unintentional injuries resulting in hospitalization. Injury categories included passengers and pedestrians injured in a motor vehicle crash, falls, drownings, burns, firearms, drug and nondrug poisonings, suffocations, and other injuries. Relative risk (RR) for injuries requiring hospitalization were calculated for children of Black, Hispanic, and Other races and ethnicities compared with White children, and then RR were further stratified by age. Excessive hospitalizations were calculated as the absolute number of hospitalizations for each race and ethnicity group that would have been avoided if each group had the same rate as White children. RESULTS: Black children were significantly more likely to be hospitalized compared with White children for all injury mechanisms except falls, and in nearly all age groups with the greatest RR for firearm injuries (RR 9.8 [95% confidence interval: 9.5-10.2]). Differences were associated with 6263 excessive hospitalizations among all racial and ethnic minority children compared with White children. CONCLUSIONS: Racial and ethnic minority children represent populations at persistent disproportionate risk for injuries resulting in hospitalization; risk that varies in important ways by injury mechanism and children's age. These findings suggest the importance of the environmental and societal exposures that may drive these differences, but other factors, such as provider bias, may also contribute.

Pediatric firearm injuries, Kansas City, 1992: a population-based study.

OBJECTIVE: To determine the morbidity, mortality, and epidemiologic features of pediatric powder-firearm injuries in a defined urban population. DESIGN AND SETTING: A population-based, descriptive epidemiologic study was conducted of firearm injuries to children in a mid-size urban community (total population: 435,178) in 1992. The population was 56% white and 39% black. Data from prehospital care providers, all city and adjacent community hospitals, and medical examiner and police records were searched for cases of firearm injury. The 1990 United States census provided denominator data. CASE DEFINITION: Subjects were all 0- to 16-year-old residents of Kansas City, Missouri who sought medical treatment at a hospital for a powder-firearm injury or who presented to the medical examiner with a fatal firearm injury in calendar year 1992. RESULTS: Seventy-two children met the case definition, for an incidence of 70 per 100,000 persons per year. There were 12 (16.7%) fatalities, for a mortality rate of 11.7 per 100,000 persons per year. Almost 10% of the patients sustained permanent disability. Mean and median ages of the patients were 14.9 years and 15.8 years, respectively; 79% were male and 82% were black. The majority of the children (63%) lived in census tracts with a high proportion of families in poverty. Black males had the highest rates of firearm injury, with a 1-year incidence of 233 per 100,000 persons per year. At younger than 12 years, the rates were equal among the races; however, for those 12 years and older, black adolescents had 13 times the risk of white adolescents (541 compared to 42 per 100,000 persons per year). The majority (71%) of injuries were due to assaults, with drive-by shootings the most frequent circumstance. The majority of unintentional injuries occurred to adolescents as the result of an unplanned discharge of a handgun as it was being placed in or removed from concealment. Among the patients, 39% were admitted to the hospital and 26% required surgery. CONCLUSIONS: 1) Black male adolescents had the highest risk of firearm injury or fatality. 2) The majority of victims lived in census tracts characterized by poverty. 3) injuries were alarmingly severe. 4) Interpersonal violence was the leading contributor to fatal and nonfatal injuries. 5) Unintentional injuries characteristically occurred during the process of weapon concealment. 6) The leading contributor to injury and death was the interaction of adolescents and guns, particularly handguns. The main implication for firearm-injury prevention in this population is the limiting of access to guns by adolescents. In addition, measures aimed at preventing violent behavior, such as education in nonviolent methods of conflict resolution, should be explored.

Unintentional perineal injury in prepubescent girls: a multicenter, prospective report of 56 girls.

OBJECTIVE: To determine the pattern of perineal injuries and frequency of hymenal involvement resulting from unintentional trauma in prepubescent girls. DESIGN: Prospective, multicenter. Observation by skilled observers. Determination of the circumstance and physical pattern of injury, with specific attention to the hymen. SETTING: Children's emergency department or acute care clinic. PATIENTS: Tanner stage 1 girls presenting with acute perineal injury. Criteria for unintentional injury: observation of the event or knowledge of the girl's engagement in a risky activity (eg, biking or climbing monkey bars) immediately before the injury. RESULTS: Fifty-six girls were evaluated. Age range: 1 to 12 years (median, 6 years; mean, 6.2 years). Associations: bicycle, 39%; other outdoor injuries, 25% (climbing apparatus, straddling an object, and falls); indoor injuries, 36% (straddling furniture and falls). Most injuries were minor. In each group the labia minora was the most frequent structure involved. The majority of injuries were anterior or lateral to the hymen. However, in 34% some or all of the injuries were posterior to the hymen. Thigh injuries were observed only in older children engaged in bicycle riding or outdoor play. In only one patient was the hymen involved. That patient was a 2 year old who fell outdoors, at a park, abducting her legs in a splits-type mechanism. She had a pinpoint abraded area on the hymenal surface at three o'clock. Otherwise, no unique pattern of injury was associated with age or circumstance of injury. CONCLUSIONS: Hymenal injuries are rarely the result of unintentional injury. The presence of a hymenal injury should suggest sexual abuse. Involvement of other perineal structures was commonly associated with unintended injury. Given the limited resources for prevention, the relative infrequency of perineal injuries and the minor nature of most of these injuries, significant preventive efforts are not justified.

Severe dog bites in children.

OBJECTIVE: We evaluated children less than 16 years of age who had dog bite injuries that resulted in hospitalization or death to determine the typical characteristics of the children, the dogs, and the injuries suffered. DESIGN: Retrospective chart review. SETTING: Three large city hospitals including Harborview Medical Center, Seattle, Washington; Children's Mercy Hospital, Kansas City, Missouri; and Mary Bridge Hospital, Tacoma, Washington. METHODS: Charts were reviewed for patient demographic data and canine data. Hospitalization data included total length of stay, need for intensive care, Injury Severity Score, the nature and extent of the injuries, procedures performed, complications, and outcome. RESULTS: Forty cases were reviewed. Most children were boys (60%) and were white (87%). The median age was 50 months. There were three deaths. Most dogs were medium-sized or large breeds and were familiar to the victim. The average hospital stay was 6 days (SD = 5), and 12 (30%) patients required a stay in the intensive care unit. Injuries to the face, head, and neck area were most common (82%). Major surgical procedures included craniotomy, exploration of the neck or abdomen, ocular procedures, and repair of fractures. CONCLUSIONS: Severe dog bites in children occur most frequently in those younger than 5 years old and involve the head and neck. Large dogs that are familiar to the child are usually involved. Young children should be closely supervised when around any dog.

Removing the pediatric cervical collar: current practice patterns.

OBJECTIVES: To identify the current practice patterns of emergency medicine practitioners and the typical criteria used in discontinuing cervical spine immobilization (CSI) in the pediatric patient. DESIGN: Mail-in survey. PARTICIPANTS: All physicians on the mailing list of the American Academy of Pediatrics Section of Emergency Medicine and an equal number of randomly chosen members of the American College of Emergency Physicians. The total number of participants was 1360. METHODS: The survey consisted of a case scenario describing a 3-year-old child brought to the emergency department with CSI. The approach to such a scenario was assessed. Surveys were mailed with self-addressed stamped envelopes; repeat mailings were sent at 4 and 8 weeks after the first mailing. Those not currently in active practice or not involved in the decision to discontinue CSI were excluded from the study. RESULTS: The response rate was 55%. Most respondents were younger than 44 years (71%), in practice less than 10 years (56%), and practiced in an urban setting (68%). Nearly two thirds (62.6%) had completed residency training in pediatrics, 24% in emergency medicine and 36% a pediatric emergency medicine fellowship. Most (63%) would discontinue CSI without obtaining radiographs. Factors associated with removal were residency training in pediatrics and being in practice for less than 10 years. The most common criteria for discontinuing CSI were normal neurological (96%) and cervical spine (98%) examinations, normal mental status (92%), and absence of neck pain (93%). CONCLUSIONS: Discontinuing CSI without obtaining radiographs is common, especially among those with residency training in pediatrics and those in practice for less than 10 years. Knowledge of current practice is essential to future development of guidelines for managing pediatric trauma patients for whom cervical spine injury is a consideration.

Pediatric acetaminophen overdose: risk factors associated with hepatocellular injury.

OBJECTIVES: To characterize demographic and clinical factors associated with pediatric acetaminophen overdose and identify risk factors for hepatocellular injury. DESIGN: Retrospective 10-year chart review. SETTING: Two regional children's hospitals. MATERIALS AND METHODS: Records of patients examined because of acetaminophen ingestion from January 1, 1988, through December 31, 1997, were reviewed. Hepatocellular injury was defined as elevation of serum aminotransferase levels greater than 2 times the reference values. Severe hepatotoxic effect was defined as hepatotoxic effect with evidence of encephalopathy and/or coagulopathy. RESULTS: Data from 322 patients (208 girls and 114 boys, aged 1-17 years) were obtained. Ingestions were intentional in 140 patients (median age, 14 years) and unintentional in 172 (median age, 2 years). Another 10 cases represented dosing errors with therapeutic intent (median age, 3.5 years). Twenty-seven patients had hepatocellular injury; of these, 4 had severe hepatotoxic effects and 1 died. Hepatocellular injury occurred in 10.0% of the dosing error group, 17.9% of the intentional group, and 0.6% of the unintentional group. No patients underwent liver transplantation. Hepatocellular injury was associated with presentation longer than 24 hours after ingestion (odds ratio [OR], 335.0; 95% confidence interval [CI], 40.8-275.0), age 10 to 17 years (OR, 36.9; 95% CI, 4.9-275.4), intentional overdose (OR, 37.2; 95% CI, 5.0-278.2), dose greater than 150 mg/kg (OR, 17.9; 95% CI, 2.3-139.2), and white race (OR, 2.8; 95% CI, 1.1-7.2). CONCLUSIONS: Intentional and unintentional acetaminophen overdoses occurred with similar frequency. Therapeutic misadventure was relatively uncommon, as was hepatocellular injury. Practitioners should have greater suspicion of acetaminophen-associated hepatocellular injury in patients who present more than 24 hours after ingestion, older children, and those who have intentional ingestion.

Bridging the emergency medical services for children information gap.

OBJECTIVE: To determine the epidemiological features of pediatric usage of prehospital emergency medical services (EMS) in a defined urban population. METHODS: Residents of Kansas City, Mo, younger than 15 years who used EMS during the calendar years 1993-1995 were included. In this geographic area there is a single provider of prehospital care; all numerator data were taken from this single source. Denominator data were provided by 1995 intercensal estimates based on the 1990 US Census. Rates were calculated as an annual average and reported as the number of children transported per 1 000 persons per year. RESULTS: There were a total of 7296 pediatric EMS transports during the study period, for an annual rate of 21.9. Infants younger than 1 year had the highest rate (47.4), followed by those aged 1 to 4 years (26.2), 10 to 14 years (17.5), and 5 to 9 years (17.3). Medicaid was the insurer for half and 27% were uninsured. One quarter of the patients used EMS more than once. Children living in ZIP codes in the lowest median income tertile were 5.8 times more likely to use EMS than those in the upper income tertile (95% confidence interval, 5.4-6.3). One third of all transports occurred between the hours of 4 and 8 PM. CONCLUSIONS: Children using the Kansas City EMS were more likely to be infants, insured by Medicaid or uninsured, and live in low-income ZIP codes. Further study is needed to determine if this increased usage is due to greater incidence and severity of illness and injury, lack of transportation, lack of education, or other factors.

Maximizing the sensitivity and specificity of pediatric trauma team activation criteria.

BACKGROUND: Care of the severely injured child requires the rapid assembly of personnel trained in pediatric trauma care. Trauma team activation criteria, which are highly sensitive and maximally specific for identifying the child who requires resuscitation, are necessary to provide rapid care to all who need it, while using resources efficiently. OBJECTIVE: To determine the sensitivity and specificity of the standard trauma team activation (TTA) criteria for identifying patients who receive resuscitation in the emergency department. METHODS: A one-year study was conducted of all patients transported by emergency medical out-of-hospital services for a trauma-related complaint. For all patients, out-of-hospital medical control operators recorded whether patients met TTA criteria and, if so, which criteria were met. Criteria included standard physiologic, anatomic, and mechanism parameters. Sensitivity and specificity for the outcome of resuscitation (volume restoration, assisted ventilation or intubation, chest tube insertion/needle decompression, operative intervention) were calculated. RESULTS: A total of 492 patients met the case definition. Two-thirds were male, the mean age was 8 years (+/-4.8 SD), and the Injury Severity Score was > or =15 in 9.3%. Trauma team activation criteria were met by 179 patients (36. 4%) and, of these, 107 met mechanism criteria only. A resuscitative intervention was received by 54 (10.9%) of the total and none in the mechanism-only group. Sensitivity and specificity of the TTA criteria for predicting receipt of a resuscitation procedure were 98. 1% and 71.2%, respectively. When mechanism criteria were excluded, the sensitivity remained 98.1% and the specificity increased to 95. 7%. CONCLUSIONS: Criteria for TTA that include patients who meet mechanism criteria only are not specific for identifying patients who receive a resuscitative intervention. Use of anatomic and physiologic criteria only results in an increase in specificity, thereby reducing overtriage while retaining a high sensitivity.

Consequences of violence. Premature death, violence recidivism, and violent criminality.

The burden of violence is born disproportionately by the youngest of our country. In this article, three important aspects of violence are discussed: premature death, violence recidivism, and violent criminality. The author emphasizes the role of the pediatrician in preventing these consequences.

The interpretation of urogenital findings in children with straddle injuries.

Because urogenital trauma frequently raises the question of sexual abuse, it is important to be able to relate the mechanism of injury to expected examination findings. This study was undertaken to characterize the trauma that results from straddling and correlate such injuries with the history, examination, and patient characteristics. The charts of 100 patients examined in an urban pediatric emergency department were reviewed; their conditions met the criteria of straddle injury--a blow to the perineum as a result of falling or striking a surface or an object with the force of one's own body weight. Ages ranged from 9 to 187 months (mean, 77.9; median, 67.2); 72% were female. Most injuries were minor lacerations and abrasions of the genitalia. Eleven percent had injury to the posterior fourchette. Hymenal and vaginal injuries were primarily caused by penetrating mechanisms. Five patients who presented with a history of straddling subsequently received the diagnosis of sexual assault based on disclosure by the patient or a witness and inconsistency of physical findings. There were no urethral or perianal injuries resulting from nonpenetrating straddle mechanisms. Straddle injuries include a variety of mostly minor urogenital injuries. Perianal, hymenal, or vaginal trauma suggests a penetrating mechanism, either unintentional or from sexual assault. An investigation for sexual assault should be initiated in the following cases: infants younger than 9 months of age; perianal, hymenal, or vaginal injury; extensive or severe injury; concurrent nonurogenital injuries; and whenever there is lack of correlation between history and physical findings.

Relationship between serum glucose and injury severity score in childhood trauma.

PURPOSE: The aim of this study was to examine the relationship between initial serum glucose and injury severity score (ISS) in children with multiple trauma. METHODS: Charts from all patients 0 to 19 years of age admitted to a children's hospital in 1995 with acute multiple trauma were reviewed. Data collected included initial serum glucose level, heart rate (HR), systolic blood pressure (SBP), Injury Severity Score (ISS), age, gender, location of trauma, and need for intravenous fluids or epinephrine. Data were analyzed using multiple linear regression. RESULTS: A total of 185 charts were reviewed. The mean ISS was 11.3; the mean glucose was 162.8 mg/dL. After adjusting for age, gender, HR, SBP, and administration of epinephrine or fluid bolus, a significant direct relationship between serum glucose and ISS was found (r = 0.52, P < .01). A stronger relationship was found in children less than 2 years old (r = 0.60, P = .04). CONCLUSIONS: A significant direct relationship exists between glucose and ISS in children with multiple trauma. High glucose values may indicate more severe injury, especially in children less than 2 years old.

Clinical factors associated with focal infiltrates in wheezing infants and toddlers.

It can be challenging to determine which findings are associated with focal infiltrates in young wheezing children. A prospective study of wheezing children < or = 18 months of age revealed focal infiltrates on chest radiograph in 23%. By use of multivariate analysis, findings significantly associated with focal infiltrates included grunting (OR 4.1, 95% CI, 2.0, 8.6) and oxygen saturation < or = 93% (OR 2.2, 95% CI, 1.1, 4.8); with a sensitivity and specificity of 12.5% and 97%, respectively. Variables not associated with focal infiltrates included first-time wheezing, fever, and tachypnea. The combination of grunting and oxygen saturation < or = 93% is highly specific and can be used to help diagnose pneumonia in wheezing infants and toddlers.

Chest radiographs in the pediatric emergency department for children < or = 18 months of age with wheezing.

There are no widely accepted predictors of pneumonia in wheezing infants and toddlers who present to the emergency department (ED). A 10-month retrospective review of ED visits of wheezing children < or = 18 months of age revealed the following chest radiograph (CXR) results: normal (21%), findings consistent with uncomplicated bronchiolitis or asthma (61%), focal infiltrates (18%), and other abnormalities (< 1%). Patients with focal infiltrates on CXR were more likely to have the following: a history of fever (p = 0.03, OR 2.1, 95% CI 1.0, 4.4), temperature > or = 38.4 degrees (p = 0.01, OR 2.5, 95% CI 1.1, 5.8) or crackles on examination (p < 0.0005, OR 3.9, 95% CI 1.7, 9.0). Selective use of CXRs has the potential to save health care dollars and limit unnecessary radiation.

Childhood injury prevention at home and play.

Unintentional injuries are the leading cause of death for children and adolescents in the United States, and they create a significant burden of disability and financial cost. If motor vehicle-associated injuries are not considered, children are most commonly injured in their home and play environments. The reduction over the past 20 years in childhood deaths related to motor vehicle injury has been significant, but rates of childhood death due to other causes, such as firearms, have increased. This review focuses on several categories of injuries other than motor vehicle injuries and highlights a few recent successful community- and practice-based injury-prevention programs. In addition, recent epidemiologic studies describing risk factors for injury-related death are discussed. Injuries due to interpersonal violence and motor vehicles are covered elsewhere.

Pediatric blunt cardiac injury: epidemiology, clinical features, and diagnosis. Pediatric Emergency Medicine Collaborative Research Committee: Working Group on Blunt Cardiac Injury.

AIM: The goal of this study was to describe the epidemiology, clinical presentation, diagnostic methods, and outcome in a large series of children with blunt cardiac injury (BCI). METHODS: A multicenter retrospective review of all individuals less than 18 years of age diagnosed with a BCI from 1983 to 1993 was conducted. Cases included all those with a discharge diagnosis of myocardial contusion, concussion, ventricular disruption, or unspecified BCI. RESULTS: A total of 184 cases of BCI were identified in 16 participating centers. The median age was 7.4 years, and 73% were male. Myocardial contusions accounted for 95% of the diagnoses. The leading mechanisms were motor vehicle crashes involving a pedestrian (39.7%) or passenger (31.0%). The majority (87%) had multiple system trauma, with a mean Injury Severity Score of 27.2 (SD +/- 14.4). Pulmonary contusions were present in 50.5% and rib fractures in 23.0%. The most common diagnostic test performed was a 12-lead electrocardiogram (EKG) (82%), followed by a MB band of creatine phosphokinase (CPK-MB) (69%) and echocardiogram (65%). All three tests were performed in 50%. In these patients, agreement among various diagnostic test pairs was fair (echocardiogram vs. EKG, kappa = 0.27) to poor (echocardiogram vs. CPK-MB, kappa = 0.07 and EKG vs. CPK-MB, kappa = 0.08). No hemodynamically stable patient who presented with a normal sinus rhythm subsequently developed a cardiac arrhythmia or cardiac failure. There were 25 deaths (13.6%), 3 of which were caused by acute pump failure secondary to massive cardiac injury. The remainder died of head or abdominal injuries. Of the 159 (86.4%) patients surviving, 8 (5% of survivors) had significant cardiac sequela, most commonly mitral or tricuspid insufficiency or ventricular septal defect. CONCLUSIONS: Pediatric BCI is usually diagnosed in the context of severe multiple system trauma and is less commonly an isolated event. Because of the lack of a standard, various diagnostic tests are used in the diagnosis of BCI, and these tests rarely agree. In hospitalized pediatric patients with BCI, unanticipated complications are rare. Significant sequela, although uncommon, do occur and follow-up of children with BCI should be ensured.

Short vertical falls in infants.

OBJECTIVE: To define injuries from short vertical falls (SVF) in infants, and to compare those with minor or no injuries to those with significant injury. DESIGN: Descriptive, retrospective chart review. SETTING: Pediatric emergency department (PED) of an urban teaching hospital. SUBJECTS: Infants < or = 10 months treated between January 1990 and December 1992 presenting with a SVF (< or = 4 feet). RESULTS: 167 patients met the definition. The mean age was 5.2 months; 56% were male. The mechanisms of injury included rolling off a bed (55%), being dropped from a caretaker's arms (20%), rolling off a couch (16%), and falling from other objects (10%). The majority of patients (85 %) had minor or no injury. Significant injuries were sustained by 15% (n = 25), including 16 with a closed head injury (12 with skull fractures), two with intracranial bleed, and seven with a long bone fracture. Subsequently, the two patients with intracranial hemorrhages were confirmed as being from child abuse. After excluding cases of suspected abuse, the only characteristic found to be independently associated with significant injury was being dropped by the caretaker (odds ratio: 6.4 vs rolling or falling from furniture, 95% CI: 2.0, 21.5). CONCLUSION: The most common mechanism of a SVF was rolling off a bed. Most patients sustained minor or no injury. No child sustained an intracranial hemorrhage from a SVF. The child with intracranial injury and/or multiple injuries warrants an investigation. Being dropped appears to be a greater risk for significant injury than rolling off or falling from furniture.

Relationship between socioeconomic factors and severe childhood injuries.

The objective was to examine the relationship between injury rates and socioeconomic factors for children in Hamilton County, Ohio, using small-area analysis. The subjects were county residents less than 15 years old who were hospitalized or died of injuries between January 1, 1993, and December 31, 1995; they were identified through a population-based trauma registry. The census tract was the unit of analysis; the rate of injury per 100,000 population was the dependent variable. Risk factors included median income, level of education, percentage below the poverty level, percentage unemployment, percentage non-Caucasian, and percentage families headed by females. There were 2,437 children meeting the case definition; injuries per census tract ranged from 0 to 2,020.2 per 100,000 per year. Census tracts with higher injury rates had lower median incomes, more people with less than a high school education, more unemployment, more families headed by females, more people living below the poverty level, and more non-Caucasians than those with lower rates. In a regression model, percentage of people living below the poverty level, percentage of those who did not graduate from high school, and percentage unemployment were significant risk factors for injuries, P < .001. Since small-area analysis examines associations on an ecological level rather than an individual level, these studies should always be interpreted with caution because an association found at the level of the census tract may not apply at the individual level. Interventions to reduce injuries should target socioeconomically disadvantaged children living below the poverty level and those in areas with fewer high school graduates and more unemployment.

Teenagers' perceptions of personal safety and the role of the emergency health care provider.

STUDY OBJECTIVE: We designed this study to determine the experiences, attitudes, and beliefs of teenagers regarding violence in their lives and to gain an understanding of the perceived role of the emergency health care professional. METHODS: A qualitative study involving 10-person focus groups was conducted in 4 cities representing urban/low socioeconomic and suburban/high socioeconomic areas. Participants were 14 or 15 years of age and were recruited from local community centers. Moderators were matched by sex to the teenagers, and groups were segmented by race and sex. A semistructured guide was developed to help facilitate the discussion. All groups were audiotaped and videotaped, and the tapes were reviewed by the investigators for reoccurring themes. RESULTS: A total of 140 adolescents (14 groups of 10) participated; one half were male. Urban teenagers expressed concerns about gangs, rape, and homicide; suburban teenagers were concerned about parental pressure and suicide. The teenagers expressed distrust of teachers, police officers, and doctors and felt safest with their parents. The emergency department was viewed as a confusing and frightening place, and participants believed that the role of the ED staff was to treat the patient's medical problem and not inquire or counsel about violence. CONCLUSION: All of the teenagers, regardless of socioeconomic status, were concerned about violence in their lives. All of the teenagers believed that the emergency department is not the place for patients to be counseled about safety and violence prevention. A better understanding of the problem of violence from the point of view of the teenager is important in refining an effective role for the emergency health care provider in adolescent violent injury prevention.

Hospitalizations for injury in New Zealand: prior injury as a risk factor for assaultive injury.

OBJECTIVES: This study sought to determine the degree to which injury hospitalization, especially for assaultive injury, is a risk for subsequent hospitalization due to assault. METHODS: A New Zealand hospitalization database was used to perform a retrospective cohort study. Exposure was defined as an injury hospitalization, stratified into assaultive and nonassaultive mechanisms. Hospitalizations for an assault during a 12-month follow-up period were measured. RESULTS: Individuals with a prior nonassaultive injury were 3.2 times more likely to be admitted for an assault than those with no injury admission (95% confidence interval [CI] = 2.7, 3.9). The relative risk associated with a prior assault was 39.5 (95% CI = 35.8, 43.5), and the subsequent admission rate did not vary significantly by sex, race, or marital or employment status. Among those readmitted for an assault, 70% were readmitted within 30 days of the initial hospitalization. CONCLUSIONS: Prior injury is a risk for serious assault, and the risk is even greater if the injury is due to assault. Risk of readmission for assault is largely independent of demographic factors and greatest within 30 days of the initial assault.