This study aims to evaluate the Language Access Systems Improvement (LASI) initiative’s impact on professional interpreter utilisation in primary care and to explore patient and clinician perspectives on professional interpreter use.

Multi methods: Quantitative natural experiment pre-LASI and post-LASI, qualitative semistructured interviews with clinicians and focus groups with patients post-LASI.

Large, academic primary care practice.

Cantonese, Mandarin, Spanish, English-speaking adult patients and their clinicians.

LASI initiative: Implementation of a clinician language proficiency test and simultaneous provision of on-demand access to professional interpreters via video medical interpretation.

Quantitative: Proportion of language discordant primary care visits which were professionally interpreted. Qualitative: Salient themes related to professional interpreter use and non-use.

The researchers categorised language concordance for 1475 visits with 152 unique clinicians; 698 were not fully language concordant (202 pre-LASI and 496 post-LASI). Professional interpreter utilisation increased (pre-LASI 57% vs post-LASI 66%; p=0.01); the visits with the lowest percentage of profssional interpreter use post-LASI were those in which clinicians and patients had partial language concordance. In inverse probability weighted analysis, restricting to 499 visits with strict estimated propensity score overlap (100% common support), post-LASI visits had higher odds of using a professional interpreter compared with pre-LASI visits (OR 2.39; 95% CI 1.04 to 5.48). Qualitative results demonstrate video interpretation was convenient and well liked by both clinicians and patients. Some partially bilingual clinicians reported frustration with patient refusal of interpreter services; others reported using the video interpreters as a backup during visits. Views of the care-partner role differed for clinicians and patients. Clinicians reported sometimes having family interpret out of convenience or habit, whereas patients reported wanting family members present for support and advocacy, not interpretation.

LASI increased utilisation of professional interpreters; however, this was least prominent for partially language concordant visits. Health systems wishing to implement LASI or similar interventions will need to support clinicians and patients with partial bilingual skills in their efforts to use professional interpreters.

HSRP20153367.