ArticlePloS one2015
Geographic Distribution of CT, MRI and PET Devices in Japan: A Longitudinal Analysis Based on National Census Data.
Article in PloS one, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 40 papers, 1 of them a synthesis that pooled it.
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Who cites it
40 citing papers in PubMed, 1 synthesis or guideline pooled it.
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- Advancing clinical MRI exams with artificial intelligence: Japan's contributions and future prospects.Japanese journal of radiology · 2025Review
- A cross-national investigation of CT, MRI, PET, mammography, and radiation therapy resources and utilization.Japanese journal of radiology · 2025Article
- Features of Undiagnosed Abdominal Pain and Diagnostic Status of Acute Hepatic Porphyria in Japan: A Retrospective Study.International journal of medical sciences · 2025Observational
- Current Status of Diagnostic Process in Asymptomatic Abdominal Aortic Aneurysm in Japan.Annals of vascular diseases · 2025Article
- Extracellular Volume by Computed Tomography Is Useful for Prediction of Prognosis in Dilated Cardiomyopathy Cases with Heart Failure with Reduced Ejection Fraction.Journal of cardiovascular development and disease · 2024Article
- Geographical Disparities in the Distribution of Community Pharmacies Providing Aseptic Preparation Services in Japan.Integrated pharmacy research & practice · 2024Article
- The impact of the Iranian health transformation plan policy on equitable access to medical imaging services in West Iran.BMC research notes · 2023Article
- The diagnostic value of dual-layer CT in the assessment of lymph nodes in lymphoma patients with PET/CT as a reference standard.Scientific reports · 2023Article
- [Large-Scale Medical Equipment - An Analysis of Supply Structures 20 Years after the Abolition of Site Planning].Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany)) · 2022Article
- Adoption of large-scale medical equipment: the impact of competition in the German inpatient sector.The European journal of health economics : HEPAC : health economics in prevention and care · 2022Article
- A 6-year audit of public-sector MR utilisation in the Western Cape province of South Africa.SA journal of radiology · 2022Article
Corrections and comments
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Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundJapan has the most CT and MRI scanners per unit population in the world; however, the geographic distribution of these technologies is currently unknown. Moreover, nothing is known of the cause-effect relationship between the number of diagnostic imaging devices and their geographic distribution.
methodsData on the number of CT, MRI and PET devices and that of their utilizations in all 1829 municipalities of Japan was generated, based on the Static Survey of Medical Institutions conducted by the government. The inter-municipality equity of the number of devices or utilizations was evaluated with Gini coefficient.
resultsBetween 2005 and 2011, the number of CT, MRI and PET devices in Japan increased by 47% (8789 to 12945), 19% (5034 to 5990) and 70% (274 to 466), respectively. Gini coefficient of the number of devices was largest for PET and smallest for CT (p for PET-MRI difference <0.001; MRI-CT difference <0.001). For all three modalities, Gini coefficient steadily decreased (p for 2011-2005 difference: <0.001 for CT; 0.003 for MRI; and <0.001 for PET). The number of devices in old models (single-detector CT, MRI<1.5 tesla, and conventional PET) decreased, while that in new models (multi-detector CT, MRI≥1.5 tesla, and PET-CT) increased. Gini coefficient of the old models increased or remained unchanged (increase rate of 9%, 3%, and -1%; p for 2011-2008 difference <0.001, 0.072, and 0.562, respectively), while Gini coefficient of the new models decreased (-10%, -9%, and -10%; p for 2011-2008 difference <0.001, <0.001, and <0.001 respectively). Similar results were observed in terms of utilizations.
conclusionsThe more abundant a modality, the more equal the modality's distribution. Any increase in the modality made its distribution more equal. The geographic distribution of the diagnostic imaging technology in Japan appears to be affected by spatial competition derived from a market force.
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