{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T13:22:19Z","timestamp":1792761739999,"version":"4.5.0"},"reference-count":41,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2019,11,1]],"date-time":"2019-11-01T00:00:00Z","timestamp":1572566400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Hypertension is one of the most prevalent diseases and is often called the \u201csilent killer\u201d because there are usually no early symptoms. Hypertension is also associated with multiple morbidities, including chronic kidney disease and cardiovascular disease. Early detection and intervention are therefore important. The current routine method for diagnosing hypertension is done using a sphygmomanometer, which can only provide intermittent blood pressure readings and can be confounded by various factors, such as white coat hypertension, time of day, exercise, or stress. Consequently, there is an increasing need for a non-invasive, cuff-less, and continuous blood pressure monitoring device. Multi-site photoplethysmography (PPG) is a promising new technology that can measure a range of features of the pulse, including the pulse transit time of the arterial pulse wave, which can be used to continuously estimate arterial blood pressure. This is achieved by detecting the pulse wave at one body site location and measuring the time it takes for it to reach a second, distal location. The purpose of this review is to analyze the current research in multi-site PPG for blood pressure assessment and provide recommendations to guide future research. In a systematic search of the literature from January 2010 to January 2019, we found 13 papers that proposed novel methods using various two-channel PPG systems and signal processing techniques to acquire blood pressure using multi-site PPG that offered promising results. However, we also found a general lack of validation in terms of sample size and diversity of populations.<\/jats:p>","DOI":"10.3390\/jcm8111827","type":"journal-article","created":{"date-parts":[[2019,11,1]],"date-time":"2019-11-01T12:30:50Z","timestamp":1572611450000},"page":"1827","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":89,"title":["Multi-Site Photoplethysmography Technology for Blood Pressure Assessment: Challenges and Recommendations"],"prefix":"10.3390","volume":"8","author":[{"given":"Gabriel","family":"Chan","sequence":"first","affiliation":[{"name":"Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachel","family":"Cooper","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manish","family":"Hosanee","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7761-3882","authenticated-orcid":false,"given":"Kaylie","family":"Welykholowa","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2868-485X","authenticated-orcid":false,"given":"Panayiotis A.","family":"Kyriacou","sequence":"additional","affiliation":[{"name":"School of Mathematics, Computer Science and Engineering, University of London, London EC1V 0HB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8077-4548","authenticated-orcid":false,"given":"Dingchang","family":"Zheng","sequence":"additional","affiliation":[{"name":"Research Center of Intelligent Healthcare, Faculty of Health and Life Science, Coventry University, Coventry CV1 5FB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7263-0533","authenticated-orcid":false,"given":"John","family":"Allen","sequence":"additional","affiliation":[{"name":"Microvascular Diagnostics, Northern Medical Physics and Clinical Engineering, Freeman Hospital, Newcastle upon Tyne NE7 7DN, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0945-2674","authenticated-orcid":false,"given":"Derek","family":"Abbott","sequence":"additional","affiliation":[{"name":"School of Electrical and Electronic Engineering, The University of Adelaide, Adelaide, SA 5005, Australia"},{"name":"Centre for Biomedical Engineering, The University of Adelaide, Adelaide, SA 5005, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1637-1079","authenticated-orcid":false,"given":"Nigel H.","family":"Lovell","sequence":"additional","affiliation":[{"name":"Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8470-8417","authenticated-orcid":false,"given":"Richard","family":"Fletcher","sequence":"additional","affiliation":[{"name":"D-Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA"},{"name":"Department of Psychiatry, University of Massachusetts Medical School, Worcester, MA 01655, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1831-0202","authenticated-orcid":false,"given":"Mohamed","family":"Elgendi","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada"},{"name":"School of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada"},{"name":"BC Children\u2019s &amp; Women\u2019s Hospital, Vancouver, BC V6H 3N1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1080\/08037051.2018.1527177","article-title":"2018 Practice Guidelines for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension","volume":"27","author":"Williams","year":"2018","journal-title":"Blood Press."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"506","DOI":"10.1016\/j.cjca.2018.02.022","article-title":"Hypertension Canada\u2019s 2018 guidelines for diagnosis, risk assessment, prevention, and treatment of hypertension in adults and children","volume":"34","author":"Nerenberg","year":"2018","journal-title":"Can. 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