When statistics outlive their geography: asynchronous propagation of a secondary medical area redefinition across Japan's national health data infrastructure — a measurable instance of institutional debt

Kunihisa Ohno
Additional contact information
Kunihisa Ohno: NPO Intensive Care Collaboration Network (ICON)

No mjzx8_v1, SocArXiv from Center for Open Science

Abstract: Health-system geographies are periodically redefined, but the national statistical products that encode them are updated on independent schedules. We report a natural experiment in how such a redefinition propagates. Effective 1 April 2024, Akita Prefecture consolidated its secondary medical areas (SMAs) from eight to three — the only SMA reorganization under Japan’s 8th Medical Plan cycle — reducing the national SMA count from 335 to 330. We examined how three national data products required for SMA-level analysis of the same reference year (2024) encoded the change, by comparing their SMA code sets and validating municipal re-aggregations against published totals. The Physician, Dentist and Pharmacist Statistics 2024 (census date 31 December 2024; released December 2025) and the Ministry of Health, Labour and Welfare’s municipality–SMA correspondence table (version dated April 2026) encode the new three-SMA definition. The 11th NDB Open Data, released June 2026, tabulates fiscal-year 2024 claims — all generated after the redefinition took effect — in the superseded eight-SMA geography. No product declares the vintage of its zone definition as metadata; the divergence surfaces only as unexplained code mismatches — and, for three zone codes reused across definitions, as silent mis-joins — observable from published artifacts alone. We interpret this as a measurable instance of institutional debt — the divergence between legally effective definitions and those encoded in infrastructure, with reconciliation labor externalized to analysts — quantifiable along three axes (lag, affected population, repairability). Contrasting England’s centrally remapped response to its 2022 commissioning-geography transition, we propose that zone-level statistics be published as versioned views over stable unit identifiers with mandatory definition-vintage metadata.

Date: 2026-08-18
References: Add references at CitEc
Citations:

Downloads: (external link)
https://osf.io/download/6a84137876ee8ecaafedd8ff/

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:osf:socarx:mjzx8_v1

DOI: 10.31235/osf.io/mjzx8_v1

Access Statistics for this paper

More papers in SocArXiv from Center for Open Science
Bibliographic data for series maintained by OSF ().