{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T09:07:06Z","timestamp":1790672826223,"version":"4.1.0"},"reference-count":24,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T00:00:00Z","timestamp":1790208000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Background: The COVID-19 pandemic profoundly affected emergency department (ED) activity worldwide, and health system constraints may persist beyond the pandemic phase. Methods: This multicenter retrospective study included all ED visits by patients aged \u226514 years at four Italian tertiary EDs in 2019 and 2024. Input, throughput, and output measures were compared using negative binomial regression and Weibull accelerated failure time models. Results: Overall, 286,298 visits occurred in 2024 and 310,900 in 2019 (adjusted change, \u22125.5%; 95% CI \u22129.8 to \u22121.0). The reduction mainly involved low-priority and daytime presentations. Despite lower input, flow metrics and crowding worsened. Door-to-physician time increased from 51 to 58 min (+21.6%; 95% CI 20.9 to 22.4). Median ED occupancy increased by 8.0% (95% CI 4.5 to 11.6), and the number of patients who left without being seen (LWBS) increased by 17.1% (95% CI 12.9 to 21.5). Total ED LOS increased from 3 h 48 min to 4 h 27 min (+15.1%; 95% CI 14.4 to 15.7). The number of admitted patients with an ED LOS of \u226512 h increased by 13.8% (95% CI 10.3 to 17.3), while ED LOS among admitted patients increased from 13 h 17 min to 19 h 21 min (+29.0%; 95% CI 27.3 to 30.8). ED LOS increased most for admissions to medical wards but decreased for critical care admissions. Conclusions: In 2024, ED volumes were lower than in 2019, whereas ED occupancy, LWBS, and ED LOS were higher, with substantial heterogeneity across centers. These findings suggest a role for hospital output constraints, but the descriptive design does not establish causality.<\/jats:p>","DOI":"10.3390\/jcm15197450","type":"journal-article","created":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T16:29:53Z","timestamp":1790267393000},"page":"7450","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Emergency Department Overcrowding Despite Lower Post-Pandemic Volumes: A Multicenter Study"],"prefix":"10.3390","volume":"15","author":[{"given":"Paolo","family":"Bima","sequence":"first","affiliation":[{"name":"Dipartimento di Scienze Mediche, Universit\u00e0 degli Studi di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovenale","family":"Moirano","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Mediche, Universit\u00e0 degli Studi di Torino, 10126 Turin, Italy"},{"name":"S.C. Epidemiologia dei Tumori U, A.O.U. Citt\u00e0 della Salute e della Scienza di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9165-7769","authenticated-orcid":false,"given":"Elvira","family":"Fanelli","sequence":"additional","affiliation":[{"name":"Medicina e Chirurgia d\u2019Accettazione e d\u2019Urgenza, Ospedale San Giovanni Bosco, 10154 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giulia","family":"Colombo","sequence":"additional","affiliation":[{"name":"Fondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico, UOC Pronto Soccorso, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8443-7880","authenticated-orcid":false,"given":"Marcello","family":"Candelli","sequence":"additional","affiliation":[{"name":"Dipartimento Scienze Emergenza, Anestesiologiche, Rianimazione, Universit\u00e0 Cattolica Sacro Cuore, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maurizio","family":"Berardino","sequence":"additional","affiliation":[{"name":"Dipartimento di Anestesia, Rianimazione ed Emergenza, Ospedale CTO, A.O.U. Citt\u00e0 della Salute e della Scienza di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Franco","family":"Apr\u00e0","sequence":"additional","affiliation":[{"name":"Medicina e Chirurgia d\u2019Accettazione e d\u2019Urgenza, Ospedale San Giovanni Bosco, 10154 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giorgio","family":"Costantino","sequence":"additional","affiliation":[{"name":"Fondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico, UOC Pronto Soccorso, 20122 Milan, Italy"},{"name":"Dipartimento di Scienze Cliniche e di Comunit\u00e0, Universit\u00e0 degli Studi di Milano, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6266-445X","authenticated-orcid":false,"given":"Francesco","family":"Franceschi","sequence":"additional","affiliation":[{"name":"Dipartimento Scienze Emergenza, Anestesiologiche, Rianimazione, Universit\u00e0 Cattolica Sacro Cuore, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefano","family":"Roggero","sequence":"additional","affiliation":[{"name":"Direzione Sanitaria Presidio Molinette, A.O.U. Citt\u00e0 della Salute e della Scienza di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Scarmozzino","sequence":"additional","affiliation":[{"name":"Direzione Sanitaria Presidio Molinette, A.O.U. Citt\u00e0 della Salute e della Scienza di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2719-1217","authenticated-orcid":false,"given":"Enrico","family":"Lupia","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Mediche, Universit\u00e0 degli Studi di Torino, 10126 Turin, Italy"},{"name":"S.C. Medicina d\u2019Urgenza U, Ospedale Molinette, A.O.U. Citt\u00e0 della Salute e della Scienza di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2142-1288","authenticated-orcid":false,"given":"Milena","family":"Maule","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Mediche, Universit\u00e0 degli Studi di Torino, 10126 Turin, Italy"},{"name":"S.C. Epidemiologia dei Tumori U, A.O.U. Citt\u00e0 della Salute e della Scienza di Torino, 10126 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7833-9632","authenticated-orcid":false,"given":"Fulvio","family":"Morello","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Mediche, Universit\u00e0 degli Studi di Torino, 10126 Turin, Italy"},{"name":"S.C. Medicina d\u2019Urgenza U, Ospedale Molinette, A.O.U. 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