Evidence map›Paper›PMID 42781887›Full record

ArticleGeriatrics & gerontology international2026

A Machine Learning-Derived Risk Scorecard for Pneumonia Hospitalization in Japanese Old-Old Adults.

Akio Shimizu, Hajime Kamiya, Masaki Tanabe, Ryota Sakamoto, Hirokazu Matsui, Ryo Momosaki

Abstract read
In one paragraph

Article in Geriatrics & gerontology international, 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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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Akio ShimizuDepartment of Rehabilitation Medicine, Mie University Hospital, Tsu, Japan.ORCID https://orcid.org/0000-0003-0244-1953
Hajime KamiyaDepartment of Public Health, Occupational Medicine, and Applied Epidemiology, Mie University Graduate School of Medicine, Tsu, Japan.ORCID https://orcid.org/0000-0003-3698-9044
Masaki TanabeDepartment of Infection Control and Infectious Disease Crisis Management, Mie University Graduate School of Medicine, Tsu, Mie, Japan.ORCID https://orcid.org/0009-0009-9626-6332
Ryota SakamotoDepartment of Medical Informatics, Mie University Hospital, Tsu, Japan.ORCID https://orcid.org/0000-0003-0411-856X
Hirokazu MatsuiDepartment of Mechanical Engineering, Mie University Graduate School of Engineering, Tsu, Japan.
Ryo MomosakiDepartment of Rehabilitation Medicine, Mie University Hospital, Tsu, Japan.ORCID https://orcid.org/0000-0003-3274-3952

Funding

Japan Society for the Promotion of Science JP25K02851Okasan Kato Culture Promotion Foundation 2025-1-30
6 · The paper itself

Abstract

aimTo develop and internally validate a machine learning-based risk scorecard for 1-year pneumonia hospitalization among community-dwelling Japanese adults aged ≥ 75 years using routinely collected frailty screening and claims data.

methodsWe conducted a retrospective cohort study of 1 098 404 community-dwelling adults aged ≥ 75 years who completed the Questionnaire for Medical Checkup of Old-Old (QMCOO) between April 2020 and March 2024, using the Late-Stage Medical Care System claims database. Data were split into training (70%) and test (30%) sets. A Super Learner ensemble of 20 base learners was developed to predict 1-year pneumonia hospitalization (ICD-10: J12-J18, J69). An independent 17-feature point-based scorecard (0-21 points) was derived from the training set with Platt calibration. Performance was evaluated by the area under the receiver operating characteristic curve (AUC), calibration slope, and calibration-in-the-large.

resultsAmong 1 098 404 participants (mean age 80.6 [SD 5.0] years; 40.3% male), 4525 (0.41%) experienced pneumonia hospitalization. On the test set, the Super Learner achieved an AUC of 0.823 (95% CI, 0.812-0.834) and the scorecard 0.786 (0.774-0.798), which showed good calibration (slope 1.017; calibration-in-the-large -0.001). Stratification into low (0-6 points; 55.6%, 0.12% event rate), moderate (7-10; 35.4%, 0.49%), and high (≥ 11; 9.0%, 1.91%) groups yielded a 15.9-fold risk gradient.

conclusionsA QMCOO-based risk scorecard showed good discrimination and calibration for predicting 1-year pneumonia hospitalization in this population. If externally validated, this tool may help identify high-risk individuals during routine health checkups and support targeted preventive assessment in primary care.

Indexed as

HospitalizationMachine LearningPneumoniaAgedAged, 80 and overEast Asian PeopleFemaleGeriatric AssessmentHumansIndependent LivingJapanMaleRetrospective StudiesRisk AssessmentRisk FactorsROC Curvefrailtymachine learningpneumoniaQMCOOrisk scorecard

Identifiers

PMID42781887
PMCPMC13602450

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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.