Abstract
The Ministry of Health, Labor, and Welfare, Japan, launched the Diagnosis Procedure Combination system in 2002. Detailed information on the Diagnosis Procedure Combination data was reported in Annals of Clinical Epidemiology in 2019. In this report, I provide updated information on the Diagnosis Procedure Combination. The data included the discharge abstracts and administrative claims data for each inpatient. Several entities (including the Ministry, academic groups, and private companies) independently collected anonymized Diagnosis Procedure Combination data. The advantages of Diagnosis Procedure Combination data include detailed process and clinical data, which enable researchers to conduct clinical epidemiology and health services research. Diagnoses are recorded using the International Classification of Diseases-10th Revision codes, and several indices based on these codes can be used. Several clinical measures are available for specific diseases including stroke, respiratory failure, heart failure, pneumonia, liver cirrhosis, pancreatitis, burns, and multiple organ failure. Scores for consciousness, activities of daily living, functional independence, and dementia are also available. Studies that use Diagnosis Procedure Combination data are interdisciplinary and include clinical medicine, epidemiology, statistics, and medical informatics.