Background: The Japanese Ministry of Health, Labour and Welfare (MHLW) released a list of public and municipal hospitals (hereinafter "the list") that are subject to reevaluation for hospital function. First, this study describes the functional differentiation status of Japanese hospital beds. Second, it evaluates the impact of the list release on the number of admissions in the listed hospitals. Methods: Firstly, the number of hospitals and beds by the function of listed and non-listed hospitals in 2019 and 2021 were described using the bed function report. The Controlled Interrupted Time Series (CITS) analyses were subsequently conducted using Diagnosis Procedure Combination (DPC) data. Hospitals were divided near the cutoff point of the list. The outcomes were the number of admissions for gastrointestinal cancer surgery, those admitted via ambulance, or with a femoral fracture per 1,000 admissions. The exposure point was the week when the list was released. Results: A decrease in the total number of beds was observed in 18.9% of the listed hospitals and 10.2% of others. Changes in bed functions were observed in 19.9% of the listed hospitals and 12.5% of others. CITS analyses showed that the rate ratio of admissions for gastrointestinal cancer surgery, those admitted via ambulance, and those with a femoral fracture in the listed hospital group after the list's release were 1.001 (95% CI: 0.998-1.004, p = 0.619), 1.001 (95% CI: 0.998-1.004, p = 0.548), and 0.998 (95% CI: 0.998-1.002, p = 0.313), respectively. Conclusion: More prominent trends of functional differentiation of hospital beds were observed in the listed hospitals. The release of the list did not impact the number of hospital admissions for gastrointestinal cancer surgery, those admitted via ambulance, or those with a femoral fracture per 1,000 admissions in the listed hospitals.

The authors have declared no competing interest.

This study was supported by Health and Labor Sciences Research Grants from the MHLW, Japan (Grant numbers: 21IA1005 and 23H00448) to Y.I. The funders played no role in the study design, data collection and analysis, publication decision, or manuscript preparation.

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Data used in this study were anonymized and approved by the Ethics Committee, Graduate School of Medicine, Kyoto University (Approval No.: R0135).

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