{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,25]],"date-time":"2026-07-25T02:24:21Z","timestamp":1784946261015,"version":"3.55.0"},"reference-count":50,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,4,23]],"date-time":"2023-04-23T00:00:00Z","timestamp":1682208000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Singapore Ministry of Health\u2019s National Medical Research Council","award":["CSASI15nov001"],"award-info":[{"award-number":["CSASI15nov001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Systems"],"abstract":"<jats:p>Globally, Emergency Care Systems (ECS) are a critical resource that needs to be used judiciously as demand can easily exceed supply capacity. Sub-optimal ECS use contributes to Emergency Department (ED) crowding; this adversely affects ECS as well as system-wide service performance. Alternate Care Service Pathways (ACSPs) are innovations intended to mitigate ED crowding by re-routing less-urgent cases to sites of care other than the ED. As in other countries, policymakers in Singapore need to respond to increasing ED utilization and are evaluating the introduction of ACSPs. However, developing ACSPs is costly, entails tinkering with established critical services, and runs the risk of unintended adverse consequences. Through a Causal Loop Diagram (CLD) developed in four stages, we present a view of the current Singapore ECS and the intended role of ACSPs in relieving its stress. This exercise suggests that to be successful ACSPs must change the prevailing mental model of the ED as a \u201cone-stop shop\u201d but should focus on integrating with primary care. The discussions stimulated by the development, critiquing, and revision of the CLD highlighted the importance of accounting for the reservations of stakeholders for changes. The CLD has enhanced shared understanding and will be used to guide quantitative simulation modeling to promote informed policy.<\/jats:p>","DOI":"10.3390\/systems11050215","type":"journal-article","created":{"date-parts":[[2023,4,24]],"date-time":"2023-04-24T02:06:11Z","timestamp":1682301971000},"page":"215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Viewing the Role of Alternate Care Service Pathways in the Emergency Care System through a Causal Loop Diagram Lens"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8280-1615","authenticated-orcid":false,"given":"Ashish","family":"Kumar","sequence":"first","affiliation":[{"name":"Health Services & Systems Research, Duke-NUS Medical School, Singapore 169857, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3361-3818","authenticated-orcid":false,"given":"Zhenghong","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Singapore General Hospital, Singapore 168753, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John Pastor","family":"Ansah","sequence":"additional","affiliation":[{"name":"Center for Community Health Integration, Case Western Reserve University, Cleveland, OH 44106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4598-1829","authenticated-orcid":false,"given":"Yih Yng","family":"Ng","sequence":"additional","affiliation":[{"name":"Home Team Medical Services Division, Ministry of Home Affairs, Singapore 329560, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1403-8993","authenticated-orcid":false,"given":"Benjamin Sieu-Hon","family":"Leong","sequence":"additional","affiliation":[{"name":"Emergency Medicine Department, National University Hospital, National University Health System, Singapore 119074, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3020-2108","authenticated-orcid":false,"given":"David Bruce","family":"Matchar","sequence":"additional","affiliation":[{"name":"Health Services & Systems Research, Duke-NUS Medical School, Singapore 169857, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7874-7612","authenticated-orcid":false,"given":"Marcus Eng Hock","family":"Ong","sequence":"additional","affiliation":[{"name":"Health Services & Systems Research, Duke-NUS Medical School, Singapore 169857, Singapore"},{"name":"Department of Emergency Medicine, Singapore General Hospital, Singapore 168753, Singapore"},{"name":"Pre-Hospital & Emergency Research Centre, Duke-NUS Medical School, Singapore 169857, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9046-5105","authenticated-orcid":false,"given":"Fahad Javaid","family":"Siddiqui","sequence":"additional","affiliation":[{"name":"Health Services & Systems Research, Duke-NUS Medical School, Singapore 169857, Singapore"},{"name":"Pre-Hospital & Emergency Research Centre, Duke-NUS Medical School, Singapore 169857, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,23]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2023, January 26). 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