Takahashi, Arata



School of Medicine, Department of Health Policy and Management (Shinanomachi)



Academic Degrees 【 Display / hide

  • 修士(診療情報管理学), 国際医療福祉大学大学院, Coursework

  • 博士(公衆衛生学), 慶應義塾大学, Coursework, 2021.03

Licenses and Qualifications 【 Display / hide

  • 診療情報管理士


Research Areas 【 Display / hide

  • Medical and hospital management

Research Keywords 【 Display / hide

  • 医療の質

  • 地域医療

  • Health Information Management


Papers 【 Display / hide

  • Estimates of the effects of centralization policy for surgery in Japan: does centralization affect the quality of healthcare for esophagectomies?

    Takahashi A., Yamamoto H., Kakeji Y., Marubashi S., Gotoh M., Seto Y., Miyata H.

    Surgery Today (Surgery Today)  51 ( 6 ) 1010 - 1019 2021.06

    ISSN  09411291

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    Purpose: This study compared the quality of healthcare before and after implementation of a policy restructuring the healthcare delivery system and estimated the impact of centralization. Methods: We used the National Clinical Database to study patients undergoing esophagectomies from 2011 to 2016. We compared the effect of centralization based on the patient background, surgical mortality, and year of surgery. Difference-in-difference methods based on the generalized estimating equation logistic regression model were used for before-and-after comparisons after adjusting for patient-level expected surgical mortality. Results: In total, 34,640 cases were identified. More cases with risk factors were noted in ultra-low-volume hospitals, where 38.4% of cases in underpopulated areas were treated, than in higher volume facilities, and the operative mortality, readmission within 30 days and length of stay were worse among patients treated in these hospitals. In centralized prefectures, the number of cases per hospital increased over time (7.2 in 2011 to 9.5 in 2016) while the crude operative mortality tended to decrease (3.4% in 2011 to 1.8% in 2016). The difference-in-difference estimator was 0.856 (95% confidence interval: 0.639–1.147, p = 0.298). Conclusion: The centralization of ultra-low-volume hospitals did not lead to a deterioration in the quality of care but rather an improving trend.

  • Profiles of institutional departments affect operative outcomes of eight gastroenterological procedures

    Konno H., Kamiya K., Takahashi A., Kumamaru H., Kakeji Y., Marubashi S., Hakamada K., Miyata H., Seto Y.

    Annals of Gastroenterological Surgery (Annals of Gastroenterological Surgery)  5 ( 3 ) 304 - 313 2021.05

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    Aim: We evaluated the association of profiles of institutional departments with operative outcomes of eight major gastroenterological procedures. Methods: We administered a 15-item online survey to 2634 institutional departments in 2016 to investigate the association of questionnaire responses with operative mortality for the procedures. The proportions of conditions met were listed according to institutional volume and classified according to annual operative cases in 1464 departments. Group A included departments with annual performance of <40 cases of the eight procedures, B 40-79 cases, C 80-199 cases, D 200-499 cases, and E ≥ 500 cases. We evaluated the number of conditions met for 10 of 15 items that could be improved by efforts of institutional departments, to assess whether the profiles of institutional departments had impacts on operative mortality. We built a multivariable logistic regression model for operative mortality with facilities categorized based on the number of conditions met and procedure-specific predicted mortality as explanatory variables using generalized estimating equation to account for facility-level clustering. We also examined how operative outcomes differed between facilities meeting nine or more conditions and those that did not. Results: We recognized meeting nine out of the 10 conditions as being a good indicator for having appropriate structural and process measures for gastroenterological surgery. The facilities meeting nine or more of the conditions had better operative mortality for all eight procedures. Conclusions: Our findings reveal that the profiles of institutional departments can reflect the outcomes of gastroenterological surgery in Japan.

  • Surgically treated gastric cancer in Japan: 2011 annual report of the national clinical database gastric cancer registry

    Suzuki S., Takahashi A., Ishikawa T., Akazawa K., Katai H., Isobe Y., Miyashiro I., Ono H., Tanabe S., Fukagawa T., Muro K., Nunobe S., Kadowaki S., Suzuki H., Irino T., Usune S., Miyata H., Kakeji Y., Suzuki S.

    Gastric Cancer (Gastric Cancer)  24 ( 3 ) 545 - 566 2021.05

    ISSN  14363291

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    Background: The National Clinical Database (NCD) nationwide registry program of gastric cancer started in 2018. The purpose of this study was to report the treatment results of the NCD registry in the form of treatment results of the real world in Japan. Methods: Patients’ characteristics, tumor features, treatments, and outcomes were collected using a web-based data entry system. We analyzed the initial NCD database for data on surgically treated gastric cancer patients in 2011. Results: A total of 30,257 patients with malignant gastric tumors were enrolled by the NCD registry program from 501 hospitals in all 47 prefectures. Of these, the status of data entry was not approved in 8.8% of the registered data, and follow-up information was missing in 1.2% of the approved cases. Excluding 1777 cases, which were not resected for primary gastric cancer, 25,306 resected cases included 44.4% of stomach surgeries recorded in the NCD. The 5 year survival rate of the resected cases was 71.3% and the operative mortality rate was 0.41%. The stage-specific 5 year survival rates were as follows: 89.6% for stage IA, 83.8% for stage IB, 77.3% for stage IIA, 69.1% for stage IIB, 58.7% for stage IIIA, 44.1% for stage IIIB, 30.1% for stage IIIC, and 13.4% for stage IV. Conclusions: The NCD gastric cancer registry program demonstrated validity for database construction. The gastric cancer registry is expected to become a nationwide registry with the dissemination of data entry system and method in the NCD.

  • Validation of data quality in a nationwide gastroenterological surgical database: The National Clinical Database site-visit and remote audits, 2016-2018

    Hasegawa H., Takahashi A., Kanaji S., Kakeji Y., Marubashi S., Konno H., Gotoh M., Miyata H., Kitagawa Y., Seto Y.

    Annals of Gastroenterological Surgery (Annals of Gastroenterological Surgery)  5 ( 3 ) 296 - 303 2021.05

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    Background and Aim: In 2015, the Japanese Society of Gastroenterological Surgery (JSGS) initiated data verification in the gastroenterological section of the National Clinical Database (NCD) and reported high accuracy of data entry. Remote audits were introduced for data validation on a trial basis in 2016 and formally accepted into use in 2017-2018. The aim of this study was to audit the data quality of the NCD gastroenterological section for 2016-2018 and to confirm the high accuracy of data in remote audits. Methods: Each year, 45-46 hospitals were selected for audit. Twenty cases were randomly selected in each hospital, and the accuracy of patient demographic and surgical outcome data (46 items) was compared with the corresponding medical records obtained by visiting the hospital (site-visit audit) or by mailing data from the hospital to the JSGS office (remote audit). Results: A total of 136 hospitals were included, of which 88 (64.7%) had a remote audit, and 124 936 items were evaluated with an overall data accuracy of 98.1%. There was no significant difference in terms of data accuracy between site-visit audit and remote audit. Accuracy, sensitivity, and specificity of mortality were 99.7%, 89.7%, 100% for site-visit audits and 99.8%, 97.3%, 100% for remote audits, respectively. Mean time spent on data verification per case of remote audits was shorter than that of site-visit audits (10.0 minutes vs 13.7 minutes, P < 0.001). Conclusion: The audits showed that NCD data are reliable and characterized by high accuracy. Remote audits may substitute site-visit audits.

  • Nationwide study of surgery for primary infected abdominal aortic and common iliac artery aneurysms

    Hosaka A., Kumamaru H., Takahashi A., Azuma N., Obara H., Miyata T., Obitsu Y., Zempo N., Miyata H., Komori K.

    The British journal of surgery (The British journal of surgery)  108 ( 3 ) 286 - 295 2021.04

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    BACKGROUND: Primary infected aneurysms of the abdominal aorta and iliac arteries are potentially life-threatening. However, because of the rarity of the disease, its pathogenesis and optimal treatment strategy remain poorly defined. METHODS: A nationwide retrospective cohort study investigated patients who underwent surgical treatment for a primary infected abdominal aortic and/or common iliac artery (CIA) aneurysm between 2011 and 2017 using a Japanese clinical registry. The study evaluated the relationships between preoperative factors and postoperative outcomes including 90-day and 3-year mortality, and persistent or recurrent aneurysm-related infection. Propensity score matching was used to compare survival between patients who underwent in situ prosthetic grafting and those who had endovascular aneurysm repair (EVAR). RESULTS: Some 862 patients were included in the analysis. Preceding infection was identified in 30.2 per cent of the patients. The median duration of postoperative follow-up was 639 days. Cumulative overall survival rates at 30 days, 90 days, 1 year, 3 years and 5 years were 94.0, 89.7, 82.6, 74.9 and 68.5 per cent respectively. Age, preoperative shock and hypoalbuminaemia were independently associated with short-term and late mortality. Compared with open repair, EVAR was more closely associated with persistent or recurrent aneurysm-related infection (odds ratio 2.76, 95 per cent c.i. 1.67 to 4.58; P < 0.001). Propensity score-matched analyses demonstrated no significant differences between EVAR and in situ graft replacement in terms of 3-year all-cause and aorta-related mortality rates (P = 0.093 and P =0.472 respectively). CONCLUSION: In patients undergoing surgical intervention for primary infected abdominal aortic and CIA aneursyms, postoperative survival rates were encouraging. Eradication of infection following EVAR appeared less likely than with open repair, but survival rates were similar in matched patients between EVAR and in situ graft replacement.

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Reviews, Commentaries, etc. 【 Display / hide

  • Publisher Correction to: Estimates of the effects of centralization policy for surgery in Japan: does centralization affect the quality of healthcare for esophagectomies? (Surgery Today, (2021), 51, 6, (1010-1019), 10.1007/s00595-021-02245-1)

    Takahashi A., Yamamoto H., Kakeji Y., Marubashi S., Gotoh M., Seto Y., Miyata H.

    Surgery Today (Surgery Today)  51 ( 6 ) 1020 - 1021 2021.06

    ISSN  09411291

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    In the original publication, under Introduction section, the sentence starting with: “In addition,…” should read as: In addition, the revised Medical Care Act of September 2015 established the "Regional Medical Cooperation Promotion Agency" system [5–6], making it possible for multiple hospitals and nursing care facilities with different management bases to share functions and improve the quality of services as if they were one hospital. Under the heading Definition of ultra-low-volume hospitals and centralization of Method section, the sentence starting with: “In this study….” should read as: In this study, based on previous studies and discussions with clinical experts, we defined an "ultra-low-volume hospital" as a hospital with fewer than two esophagectomy cases per year [11, 26]. In Table 3, the value “0.856 (95% CI 0.639–1.147) *p = 0.298” should be listed under the year “2014”. The updated Table 3 is given in this correction.


Courses Taught 【 Display / hide








Memberships in Academic Societies 【 Display / hide

  • 日本診療情報管理学会

  • 日本臨床疫学会

  • 日本医師事務作業補助研究会