People who experience human trafficking (HT) visit emergency departments (ED). The International Classification of Diseases, Clinical Modification (ICD-10-CM) introduced codes to document HT in June 2018. The aim of this study is to identify characteristics of ED patients who experienced forced labor or sexual exploitation as a documented external cause of morbidity in US visits.

Nationally representative surveillance based on patient visits to 989 hospital-owned EDs in the Nationwide Emergency Department Sample in 2019 became available in 2021. Eight ICD-10-CM codes to classify HT as an external cause of morbidity were combined into one HT variable for analysis in 2021–2022.

A weighted count of 517 of 33.1 million ED visits (0.0016%) documented HT as an external cause of morbidity. Of them, sexual exploitation (71.6%) was documented more frequently than labor exploitation (28.4%). Most HT-related codes were visits by females (87.3%) from large metropolitan areas, and identified as white. Approximately 40% of visits were from ZIP codes with a median household income less than $48,000 annually. Relative to all other ED visits, patients with HT as an external cause of morbidity had higher odds of being female (OR = 6.54, 95% CI:3.59, 11.92) and being a minor (OR = 1.76, 95% CI:1.02, 3.04).

HT was rarely documented as an external cause of morbidity in 989 hospitals' ED visits from a nationally representative sample in 2019. Documentation of recently added HT ICD-10-CM codes does not appear to have been implemented sufficiently to yield an unbiased representation of those who experienced HT and presented in the ED. Efforts to enhance the utility of ICD-10-CM HT codes for surveillance and documentation must first address ED personnel training on identification and response to HT. In doing so, ED personnel also need to address ethical concerns (e.g. stigma, confidentiality, risk of patient harm) and allow for informed consent among trafficked patients in order to be scaled up responsibly.