Background: Despite federal mandates requiring qualified interpreter use, ad hoc interpreters, untrained individuals such as family members or bilingual staff, continue to be used in clinical care for patients with non-English language preference (NELP). Prior studies rely primarily on self-report or administrative data, leaving gaps in our understanding of how and when ad hoc interpretation is documented in real-world practice.
Objective: To characterize the frequency, documentation, and contextual factors associated with untrained ad hoc interpreter use in inpatient medicine settings.
Methods: We conducted a retrospective cohort study of adults with NELP admitted to a general medicine service at a large academic medical center between 2019 and 2023. We analyzed clinical notes using a large language model-based approach to identify documentation of interpreter use. Ad hoc interpretation cases were manually validated and categorized by interpretive role and documented rationale.
Results: Among 23,245 clinical notes from 2176 admissions involving 1379 patients with NELP, professional interpreter services were documented in 5921 notes (25.5% of notes). Ad hoc interpreter use was explicitly documented in 600 notes (2.6% of notes), across 324 admissions (14.9% of admissions) and 223 patients (16.2% of patients). Most ad hoc interpreter documentation involved family members (64.7%), and 7.7% occurred in conjunction with professional interpreters. Admissions with documented ad hoc interpreter use involved older patients, longer hospital stays, and higher comorbidity burden. Documented ad hoc interpreter use was more prevalent among non-Spanish language groups and increased with length of stay; nearly 75% of ad hoc interpreter notes lacked a documented rationale.
Conclusion: Ad hoc interpreter use was relatively common among inpatients with NELP, particularly for less common languages and longer lengths of stay, and was most often provided by family members. Gaps in documented rationales for ad hoc interpreter use reveal systemic issues in language access workflows and underscore the need for improved access to professional interpretation, standardized documentation, and greater use of qualified bilingual staff to ensure equitable, policy-compliant communication for all language groups.
© 2026. The Author(s).