Evidence map›Paper›PMID 42554897›Full record

Observational studyJournal of medical systems2026

Temporal Variability in Diagnosis Code Distributions Across Extraction Time Points in a Multicenter Integrated EHR Database: A Snapshot Comparison Study.

Kyunghee Lee, Chihiro Kumagai, Masato Komuro, Kengo Miyo, Hiroyuki Hoshimoto

Abstract readObservational StudyComparative StudyMulticenter Study
In one paragraph

Observational study in Journal of medical systems, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Kyunghee LeeJapan Institute for Health Security, 1-12-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan. ri.k@jihs.go.jp.ORCID http://orcid.org/0009-0009-5323-6811
Chihiro KumagaiJapan Institute for Health Security, 1-12-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan.
Masato KomuroJapan Institute for Health Security, 1-12-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan.ORCID http://orcid.org/0000-0002-3445-9595
Kengo MiyoJapan Institute for Health Security, 1-12-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan.ORCID http://orcid.org/0000-0001-6111-3154
Hiroyuki HoshimotoJapan Institute for Health Security, 1-12-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan. hoshimoto.h@jihs.go.jp.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

EHR data are widely used in clinical research; however, their temporal stability remains poorly understood. This study aimed to evaluate temporal variability in EHR data arising from differences in extraction time points. We conducted a retrospective, descriptive, observational study using diagnostic data from a multicenter integrated EHR database in Japan. The target period was 2022, and diagnosis records with a start date within this period were extracted at three time points: October 2023, October 2024, and October 2025. Diagnoses were mapped to the three-character level of the International Classification of Diseases, 10th Revision (ICD-10). Changes in diagnosis code distributions were quantified using the Jensen-Shannon distance (JSD). Changes in record counts per ICD-10 code between 2023 and 2025 were also evaluated. Five facilities were included in the analysis. In the integrated dataset, variations in total records and unique patients were minimal (total records: +0.06% in 2024 and + 0.05% in 2025; unique patients: +0.06% in 2024 and + 0.02% in 2025). JSD values for ICD-10 distributions were non-zero across all facilities, indicating that diagnosis code distributions differed across extraction time points even for the same target period. Across all facilities excluding Facility C, JSD was 0.0022 in 2024 and 0.0026 in 2025 relative to the 2023 baseline. In contrast, Facility C exhibited a markedly larger JSD in 2024 (0.0310), which persisted at a similar level in 2025 (0.0317). At the code level, H61 showed the largest absolute change (- 266 records; -19.98%). Overall, acute conditions tended to decrease, whereas chronic conditions increased across extraction time points. EHR data exhibit temporal variability across extraction time points, even for the same target period. These findings highlight the importance of documenting extraction timing and dataset version, and suggest the need for study designs that explicitly account for such variability.

Indexed as

Electronic Health RecordsDatabases, FactualHumansInternational Classification of DiseasesJapanRetrospective StudiesTime FactorsData qualityElectronic health recordsICD-10Multicenter studyReproducibilityTemporal variability

Identifiers

PMID42554897
PMCPMC13442496

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.