{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:47:35Z","timestamp":1760150855823,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,1,22]],"date-time":"2022-01-22T00:00:00Z","timestamp":1642809600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>There is a need to rapidly screen individuals for heat strain and fever using skin temperature (Tsk) as an index of deep body temperature (Tb). This study\u2019s aim was to assess whether Tsk could serve as an accurate and valid index of Tb during a simulated heatwave. Seven participants maintained a continuous schedule over 9-days, in 3-day parts; pre-\/post-HW (25.4 \u00b0C), simulated-HW (35.4 \u00b0C). Contact thermistors measured Tsk (Tforehead, Tfinger); radio pills measured gastrointestinal temperature (Tgi). Proximal-distal temperature gradients (\u0394Tforehead\u2013finger) were also measured. Measurements were grouped into ambient conditions: 22, 25, and 35 \u00b0C. Tgi and Tforehead only displayed a significant relationship in 22 \u00b0C (r: 0.591; p &lt; 0.001) and 25 \u00b0C (r: 0.408; p &lt; 0.001) conditions. A linear regression of all conditions identified Tforehead and \u0394Tforehead\u2013finger as significant predictors of Tgi (r2: 0.588; F: 125.771; p &lt; 0.001), producing a root mean square error of 0.26 \u00b0C. Additional residual analysis identified Tforehead to be responsible for a plateau in Tgi prediction above 37 \u00b0C. Contact Tforehead was shown to be a statistically suitable indicator of Tgi in non-HW conditions; however, an error of ~1 \u00b0C makes this physiologically redundant. The measurement of multiple sites may improve Tb prediction, though it is still physiologically unsuitable, especially at higher ambient temperatures.<\/jats:p>","DOI":"10.3390\/s22030826","type":"journal-article","created":{"date-parts":[[2022,1,23]],"date-time":"2022-01-23T20:36:27Z","timestamp":1642970187000},"page":"826","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Predicting Deep Body Temperature (Tb) from Forehead Skin Temperature: Tb or Not Tb?"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6329-0274","authenticated-orcid":false,"given":"Jason T.","family":"Fisher","sequence":"first","affiliation":[{"name":"Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia"},{"name":"International Postgraduate School Jozef Stefan, Jamova 39, SI-1000 Ljubljana, Slovenia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8382-7449","authenticated-orcid":false,"given":"Ur\u0161a","family":"Ciuha","sequence":"additional","affiliation":[{"name":"Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7928-8451","authenticated-orcid":false,"given":"Michael J.","family":"Tipton","sequence":"additional","affiliation":[{"name":"School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth PO1 2EF, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5460-8167","authenticated-orcid":false,"given":"Leonidas G.","family":"Ioannou","sequence":"additional","affiliation":[{"name":"Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5930-2159","authenticated-orcid":false,"given":"Igor B.","family":"Mekjavic","sequence":"additional","affiliation":[{"name":"Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1016\/j.jtherbio.2008.03.004","article-title":"A non-invasive device to continuously determine heat strain in humans","volume":"33","author":"Gunga","year":"2008","journal-title":"J. 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