Coding-based discrepancies between admission and discharge diagnoses of paediatric patients in China: an observational study of more than 7 million hospitalisation records.

Abstract

To determine the rate of coding-based discrepancies between admission and discharge diagnoses in hospitalised paediatric patients in China, identify associated factors and investigate the impact on length of stay (LOS) and total hospitalisation expenses. Retrospective observational study. 30 tertiary children's hospitals across seven geographical regions of China, 2016-2021. 7 575 622 hospitalisation records aged under 19 years. Primary outcome: proportion of hospitalisations with inconsistent admission and discharge diagnoses (defined by International Classification of Diseases-10 code mismatch). LOS and total hospitalisation expenses. 2 040 457 records (26.93%) had inconsistent diagnosis code, with a significant increasing trend over time (Cochran-Armitage Z=137.95, p<0.001). Higher odds of coding inconsistency were associated with adolescents aged 13-18 years (OR 1.216, 95% CI 1.198 to 1.233), emergency department admission (OR 1.115, 95% CI 1.110 to 1.120), greater comorbidity burden (OR 1.178, 95% CI 1.177 to 1.179 per additional comorbidity) and hospital location in Middle China (OR 1.688, 95% CI 1.675 to 1.700). Coding inconsistency rates were highest for infectious and parasitic diseases (45.06%) and circulatory system diseases (41.25%). After adjustment for potential confounders, diagnostic inconsistency was independently associated with longer LOS (β=0.082, p<0.001) and higher total expenses (β=0.058, p<0.001). These findings highlight opportunities to enhance coding accuracy and optimise clinical workflows in paediatric healthcare in China. Enhancing diagnostic consistency can optimise resource utilisation, reduce costs and improve patient outcomes.