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Ng SH, Tiew PY, Chotirmall SH, Chen W, Abisheganaden J. Two distinct healthcare utilisation trajectories prior to a COPD diagnosis in a multi-ethnic Asian population: a comparison of transient and chronic users. BMJ Open Respiratory Research. 2026;13:e003686. https://doi.org/10.1136/bmjresp-2025-003686