Department of Research & Evaluation News

A study of nearly 2 million pediatric Kaiser Permanente members reinforces known links between children’s chances of experiencing a firearm injury and certain risk factors — especially being an adolescent male. The study, which appeared recently in Academic Pediatrics, addresses a number of additional risk factors, providing a broad view of the risk of firearm injury for young people under 18.

“Pediatric firearm injury is a public health issue that I feel very strongly about helping to address,” said the study’s lead author, Sonya Negriff, PhD, a developmental psychologist and research scientist at the Kaiser Permanente Southern California Department of Research & Evaluation. “Our findings bolster confidence in known risk factors and could help target prevention efforts among the most vulnerable youth.”

The study is one way Kaiser Permanente is working toward preventing and reducing the impact of firearm injuries.

“Firearm injury is a serious but relatively rare event, so we need data from a large number of patients to tackle it,” said the study’s senior author Rulin Hechter, MD, PhD, an infectious disease epidemiologist at Research & Evaluation. “The large patient population at Kaiser Permanente Southern California gives us an edge in conducting firearms research to benefit not only our members, but people throughout our region and beyond.”

A big-picture investigation

Most prior research on firearm injury has focused on fairly narrow sets of risk factors using data from small numbers of patients. Larger studies that consider a broader constellation of risk factors all at once — and differentiate between self-inflicted versus non-self-inflicted injuries — have been lacking.

To help fill that gap, a multidisciplinary team including Dr. Negriff and Dr. Hechter conducted an analysis of electronic health record data from 1,889,182 children younger than 18 who had received any kind of care at Kaiser Permanente Southern California from 2010 through 2018.

The researchers used the data to investigate potential links between firearm injuries and several different risk factors, including age, gender, race and ethnicity, Medicaid status, mental health, substance use disorder, medical comorbidities, and educational achievement levels in a child’s residential neighborhood.

The analysis showed that children ages 12 to 17 were at significantly higher risk of non-self-inflicted firearm injury than children ages 0 to 5 years old. Male gender, being Black or Hispanic (versus white), being a Medicaid recipient, living in a neighborhood with lower education levels, and being diagnosed with a substance use disorder were also associated with increased risk of non-self-inflicted firearm injury.

The only statistically significant factors associated with self-inflicted firearm injury were being male and being an adolescent ages 12 to 17. However, Dr. Negriff cautioned that this does not contradict findings from prior studies that have linked mental health to self-inflicted firearm injury.

“Self-inflicted firearm injury is quite rare, which limits our ability to detect statistical associations even in large studies,” she said. “That is why it is important to accumulate evidence from various different studies like ours.”

Building knowledge to inform action

These findings highlight the influence of multiple kinds of risk factors for pediatric firearm injury, which could help guide efforts to reduce risk.

“Our study underscores the need to screen pediatric patients for risk of either self-inflicted or non-self-inflicted firearm injury,” Dr. Hechter said.

In addition to individual screening, medical centers in higher-risk locations can provide services that address risk factors at a broader population level. “This research reaffirms that it is important to consider the contextual environment in which non-self-inflicted firearm injuries occur and the systemic factors that contribute to environments where, for instance, kids may face higher risk of firearm injury from just walking to school,” Dr. Negriff said.

This study is one of several funded by a grant awarded to Dr. Hechter by the Kaiser Permanente Office of Community Health’s Firearm Injury Prevention Program. Upcoming papers will report trends in firearm injury rates, an investigation of risk factors for adult firearm injuries, and a machine-learning analysis to further identify and deepen understanding of risk factors for firearm injuries in children and adults.

Kaiser Permanente also recently launched the Center for Gun Violence Research and Education, which aims to prevent and reduce the impact of gun violence across the United States.

“Our research and this new nationwide effort are all part of the long-term commitment that Kaiser Permanente has made to reduce firearm injury and death,” Dr. Hechter said.

In addition to Dr. Negriff and Dr. Hechter, other authors on the study were Margo Sidell, ScD; Claudia Nau, PhD; Adam L. Sharp, MD, MSc; Corinna Koebnick, MS, PhD,; Richard Contreras, MS; and Deborah S. Ling Grant, PhD, MBA, of Kaiser Permanente Southern California Department of Research & Evaluation; and Johnathan K. Kim, MD, of Kaiser Permanente Southern California Department of Psychiatry.