{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T03:55:43Z","timestamp":1790654143487,"version":"4.1.0"},"reference-count":23,"publisher":"Springer Science and Business Media LLC","issue":"10","license":[{"start":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T00:00:00Z","timestamp":1781481600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T00:00:00Z","timestamp":1781481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Jpn J Radiol"],"published-print":{"date-parts":[[2026,10]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>To evaluate whether Radiology Information System (RIS) action log-guided continuous quality improvement (KAIZEN) improved CT operational efficiency.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Materials and methods<\/jats:title>\n                    <jats:p>This single-center retrospective before-and-after quality improvement study included 150,540 weekday CT examinations from 2018 to 2022. Five workflow interventions were introduced sequentially from January through February 2021. Daily median examination time, daily median patient entry\/exit time, and the end time of the final weekday CT examination were analyzed using segmented interrupted time-series regression with interruptions in January 2020 and January 2021 and heteroskedasticity- and autocorrelation-consistent standard errors. Key performance indicator (KPI) models were adjusted for daily volume, day of the week, and inpatient proportion; unadjusted models were used as sensitivity analyses.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Daily median examination time decreased from 351\u00a0s at baseline to 328\u00a0s after KAIZEN. KAIZEN initiation was associated with an immediate reduction in adjusted examination time (\u2212\u200917.37\u00a0s; 95% CI,\u2009\u2212\u200931.35 to\u2009\u2212\u20093.40\u00a0s;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.015), whereas the unadjusted sensitivity analysis was directionally consistent but non-significant (\u2212\u200911.07\u00a0s;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.060). Entry\/exit time decreased from 216 to 198\u00a0s and showed a significant adjusted immediate reduction (\u2212\u200915.99\u00a0s; 95% CI,\u2009\u2212\u200923.93 to\u2009\u2212\u20098.04\u00a0s;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001), consistent with the unadjusted analysis. The final weekday CT examination ended 12.49\u00a0min earlier (95% CI,\u2009\u2212\u200922.11 to\u2009\u2212\u20092.87\u00a0min;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.011).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>RIS action log-guided KAIZEN was temporally associated with shorter turnover, earlier completion of weekday operations, and reduced adjusted examination time. Replication in diverse settings is warranted.<\/jats:p>\n                    <jats:p>Secondary Abstract.<\/jats:p>\n                    <jats:p>In this single-center study, RIS action log-guided KAIZEN was temporally associated with shorter CT patient entry\/exit time, earlier weekday completion, and reduced adjusted examination time, supporting routine log-based workflow monitoring.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s11604-026-02034-1","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T07:40:27Z","timestamp":1781509227000},"page":"1874-1885","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Optimizing efficiency in CT services: a data-driven approach using action logs from the radiology information system"],"prefix":"10.1007","volume":"44","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0714-2397","authenticated-orcid":false,"given":"Shingo","family":"Kayano","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7239-3152","authenticated-orcid":false,"given":"Hideki","family":"Ota","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshihiko","family":"Takubo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiromu","family":"Mashiko","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kosuke","family":"Usui","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuki","family":"Shimada","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-9755-9394","authenticated-orcid":false,"given":"Minori","family":"Hoshika-Kayano","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0931-9942","authenticated-orcid":false,"given":"Kei","family":"Takase","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,15]]},"reference":[{"key":"2034_CR1","doi-asserted-by":"publisher","unstructured":"Computed tomography (CT) scanners. 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No patient demographic data or personally identifiable information were collected. According to institutional policy and the Japanese \u201cEthical Guidelines for Life Science and Medical Research Involving Human Subjects,\u201d this project was considered exempt from formal ethical review. Informed consent was not applicable.","order":1,"name":"Ethics","label":"Ethics approval","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Kei Takase and Hideki Ota were supported by a research grant from Canon Medical Systems. The other authors report no conflicts of interest.","order":2,"name":"Ethics","label":"Competing interests","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","order":3,"name":"Ethics","label":"Consent to publish","group":{"name":"EthicsHeading","label":"Declarations"}}]}}