{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,30]],"date-time":"2025-10-30T07:15:07Z","timestamp":1761808507371,"version":"build-2065373602"},"reference-count":56,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,4,5]],"date-time":"2022-04-05T00:00:00Z","timestamp":1649116800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["PI17\/00856"],"award-info":[{"award-number":["PI17\/00856"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Body temperature is usually employed in clinical practice by strict binary thresholding, aiming to classify patients as having fever or not. In the last years, other approaches based on the continuous analysis of body temperature time series have emerged. These are not only based on absolute thresholds but also on patterns and temporal dynamics of these time series, thus providing promising tools for early diagnosis. The present study applies three time series entropy calculation methods (Slope Entropy, Approximate Entropy, and Sample Entropy) to body temperature records of patients with bacterial infections and other causes of fever in search of possible differences that could be exploited for automatic classification. In the comparative analysis, Slope Entropy proved to be a stable and robust method that could bring higher sensitivity to the realm of entropy tools applied in this context of clinical thermometry. This method was able to find statistically significant differences between the two classes analyzed in all experiments, with sensitivity and specificity above 70% in most cases.<\/jats:p>","DOI":"10.3390\/e24040510","type":"journal-article","created":{"date-parts":[[2022,4,5]],"date-time":"2022-04-05T06:01:34Z","timestamp":1649138494000},"page":"510","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Discriminating Bacterial Infection from Other Causes of Fever Using Body Temperature Entropy Analysis"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5553-8372","authenticated-orcid":false,"given":"Borja","family":"Vargas","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, Hospital Universitario de M\u00f3stoles, 28935 Mostoles, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0076-0515","authenticated-orcid":false,"given":"David","family":"Cuesta-Frau","sequence":"additional","affiliation":[{"name":"Technological Institute of Informatics, Universitat Polit\u00e8cnica de Val\u00e8ncia, Alcoi Campus, 03801 Alcoi, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paula","family":"Gonz\u00e1lez-L\u00f3pez","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Hospital Universitario de M\u00f3stoles, 28935 Mostoles, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mar\u00eda-Jos\u00e9","family":"Fern\u00e1ndez-Cotarelo","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Hospital Universitario de M\u00f3stoles, 28935 Mostoles, Spain"},{"name":"Faculty of Health Sciences, Universidad Rey Juan Carlos, 28922 Alcorcon, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"\u00d3scar","family":"V\u00e1zquez-G\u00f3mez","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Hospital Universitario de M\u00f3stoles, 28935 Mostoles, Spain"},{"name":"Faculty of Health Sciences, Universidad Rey Juan Carlos, 28922 Alcorcon, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2784-4150","authenticated-orcid":false,"given":"Ana","family":"Col\u00e1s","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Manuel","family":"Varela","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Hospital Universitario de M\u00f3stoles, 28935 Mostoles, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s13049-015-0178-z","article-title":"Temperature measurements in trauma patients: Is the ear the key to the core?","volume":"23","author":"Uleberg","year":"2015","journal-title":"Scand. 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