To examine the distribution and frequency of International Classification of Diseases, 10th Revision (ICD-10), codes in emergency departments (EDs) across Malaysia, providing insights into the most common diagnoses. The aim is to support the development of a principal diagnosis short list for implementing ED-specific diagnosis-related groups (DRGs) to enhance resource allocation and healthcare efficiency.

A cross-sectional study conducted as part of a functional exercise by the Ministry of Health Malaysia, with systematic retrospective data collection over a 6-week period in 2022.

13 public emergency hospitals across Malaysia, representing state, major specialist, minor specialist and non-specialist hospitals, including facilities from Sabah and Sarawak for geographical diversity.

10 247 ED visit records were collected through systematic random sampling, of which 9942 complete and valid records were retained for analysis after the exclusion of incomplete or erroneous entries.

The study included 9942 ED patient records from 13 public hospitals across Malaysia over a 6-week period. Of these, 54.4% were male, and 45.5% were female. Malaysian citizens comprised 96.1% of the study population. The most frequently reported diagnoses were respiratory diseases (21.2%), followed by injuries and poisoning (13.2%) and digestive system disorders (8.4%). A total of 946 unique ICD-10 codes were identified, with 73.7% used fewer than five times. The top 20 diagnoses accounted for 42.9% of all records. Acute upper respiratory infection (J06.9) was the most commonly reported diagnosis (961 cases), followed by COVID-19 (U07.1, 608 cases) and gastroenteritis of unspecified origin (A09.9, 313 cases). The data demonstrated variation in the distribution of ICD-10 diagnoses across participating hospitals, highlighting key diagnostic categories relevant for future DRG development.

This study highlights the diversity of diagnoses in Malaysian EDs and underscores the need for tailored DRGs to optimise healthcare resource allocation. The findings suggest that a principal diagnosis short list may support future efforts to improve classification consistency and inform resource planning, although its effect warrants empirical evaluation. Given the concentration of diagnoses within a limited number of ICD-10 codes, implementing DRGs in emergency care is both feasible and necessary. Future research should expand data collection to capture seasonal trends and refine the principal diagnosis list to further support DRG categorisation and ensure its applicability across varying healthcare demands.