Plain language in healthcare interpreting. Reflections from interpreter-mediated consultations

Current models of care emphasise patient participation, which depends on patients' understanding of specialised medical knowledge and their ability to navigate complex healthcare systems. In this context, plain language has been promoted to enhance comprehension, but it has been mainly examined in written communication and its role in interpreter-mediated healthcare interactions remains underexplored. This study addresses this gap by analysing healthcare interpreting practices through the lens of plain language, conceptualised here as a form of epistemic mediation within structurally unequal healthcare systems. Drawing on 101 interpreter-mediated consultations collected in 2017 in a hospital in Madrid (Spain) and analysed through a secondary qualitative approach, 106 interpreter interventions were identified and classified using thematic analysis. As a result, we identified four interrelated categories that shape how medical knowledge is communicated and understood in interaction: making specialised knowledge accessible, managing information and epistemic boundaries, negotiating understanding, and reconfiguring meaning across sociocultural frameworks. Although these practices may enhance patient understanding and support navigation across institutional and sociocultural contexts, they also raise questions concerning accuracy, professional boundaries and paternalism. Therefore, the study reveals the tension between promoting accessibility and maintaining precision, and between supporting patients respectfully and enabling their autonomy within asymmetrical healthcare encounters. In light of these findings, the study proposes understanding healthcare interpreting as an epistemic process through which specialised knowledge is negotiated, redistributed and, at times, transformed.