{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T09:06:37Z","timestamp":1777021597971,"version":"3.51.4"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,7,21]],"date-time":"2021-07-21T00:00:00Z","timestamp":1626825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["156_596835053"],"award-info":[{"award-number":["156_596835053"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Horizon 2020","award":["101016203"],"award-info":[{"award-number":["101016203"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Forecasting COVID-19 disease severity is key to supporting clinical decision making and assisting resource allocation, particularly in intensive care units (ICUs). Here, we investigated the utility of time- and frequency-related features of the backscattered signal of serum patient samples to predict COVID-19 disease severity immediately after diagnosis. ICU admission was the primary outcome used to define disease severity. We developed a stacking ensemble machine learning model including the backscattered signal features (optical fingerprint), patient comorbidities, and age (AUROC = 0.80), which significantly outperformed the predictive value of clinical and laboratory variables available at hospital admission (AUROC = 0.71). The information derived from patient optical fingerprints was not strongly correlated with any clinical\/laboratory variable, suggesting that optical fingerprinting brings unique information for COVID-19 severity risk assessment. Optical fingerprinting is a label-free, real-time, and low-cost technology that can be easily integrated as a front-line tool to facilitate the triage and clinical management of COVID-19 patients.<\/jats:p>","DOI":"10.3390\/diagnostics11081309","type":"journal-article","created":{"date-parts":[[2021,7,21]],"date-time":"2021-07-21T11:53:23Z","timestamp":1626868403000},"page":"1309","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Forecasting COVID-19 Severity by Intelligent Optical Fingerprinting of Blood Samples"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0552-5266","authenticated-orcid":false,"given":"Sim\u00e3o P.","family":"Faria","sequence":"first","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Cristiana","family":"Carpinteiro","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3604-7786","authenticated-orcid":false,"given":"Vanessa","family":"Pinto","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Sandra M.","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Jos\u00e9","family":"Alves","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Filipe","family":"Marques","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Marta","family":"Louren\u00e7o","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Paulo H.","family":"Santos","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Ang\u00e9lica","family":"Ramos","sequence":"additional","affiliation":[{"name":"Servi\u00e7o de Patologia Cl\u00ednica, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"},{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica da Universidade do Porto, 4050-600 Porto, Portugal"}]},{"given":"Maria J.","family":"Cardoso","sequence":"additional","affiliation":[{"name":"Servi\u00e7o de Patologia Cl\u00ednica, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"},{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica da Universidade do Porto, 4050-600 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4836-6311","authenticated-orcid":false,"given":"Jo\u00e3o T.","family":"Guimar\u00e3es","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"Servi\u00e7o de Patologia Cl\u00ednica, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, 4200-319 Porto, Portugal"},{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica da Universidade do Porto, 4050-600 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5390-3807","authenticated-orcid":false,"given":"Sara","family":"Rocha","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1148-2159","authenticated-orcid":false,"given":"Paula","family":"Sampaio","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"i3S\u2014Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, Universidade do Porto, 4200-135 Porto, Portugal"},{"name":"IBMC\u2014Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal"}]},{"given":"David A.","family":"Clifton","sequence":"additional","affiliation":[{"name":"Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford OX3 7DQ, UK"}]},{"given":"Mehak","family":"Mumtaz","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Joana S.","family":"Paiva","sequence":"additional","affiliation":[{"name":"iLoF\u2014Intelligent Lab on Fiber, Limited, Oxford OX1 2EW, UK"},{"name":"Departamento de Bioqu\u00edmica, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"},{"name":"Instituto de Ci\u00eancias Biom\u00e9dicas Abel Salazar, University of Porto, 4200-319 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2052","DOI":"10.1001\/jama.2020.6775","article-title":"Presenting characteristics, comorbidities and outcomes among 5700 patients hospitalized With COVID-19 in the New York City area","volume":"323","author":"Richardson","year":"2020","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1089","DOI":"10.1007\/s00134-020-06062-x","article-title":"High risk of thrombosis in patients with severe SARS-CoV-2 infection: A multicenter prospective cohort study","volume":"46","author":"Helms","year":"2020","journal-title":"Intensive Care Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"683","DOI":"10.1001\/jamaneurol.2020.1127","article-title":"Neurologic manifestations of hospitalized 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