{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,25]],"date-time":"2026-07-25T23:28:20Z","timestamp":1785022100264,"version":"3.55.0"},"reference-count":47,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2025,9,10]],"date-time":"2025-09-10T00:00:00Z","timestamp":1757462400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100006108","name":"National Center for Advancing Translational Sciences","doi-asserted-by":"publisher","award":["UL1TR002378"],"award-info":[{"award-number":["UL1TR002378"]}],"id":[{"id":"10.13039\/100006108","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"\n Background<\/jats:title>\n Erythema, an early visual indicator of tissue damage preceding pressure injuries (PrIs), presents as redness in light skin tones but is harder to detect in dark skin tones. While thermography shows promise for early PrI detection, validation across different skin tones remains limited. Furthermore, most protocols and models have been developed under highly controlled conditions.<\/jats:p>\n <\/jats:sec>\n \n Objective<\/jats:title>\n To evaluate how environmental and technical factors (i.e., patient positioning, lighting, distance, camera type) and skin tone impact thermal imaging measurements and temperature change.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n This pre-post experimental study enrolled 35 healthy adults (30 with Monk Skin Tone Scale \u22656). Melanin Index was measured on the volar forearm using the SkinColorCatch\n \u00ae<\/jats:sup>\n . After baseline imaging, a 15.5\u00b0C cooling stone was placed on one posterior superior iliac spine (PSIS) for 5 minutes. Thermal images were then collected with either the FLIR E8-XT or the FLIR ONE Pro camera under varied conditions: two lighting types (overhead room versus localized LED ring light), three postures (side-lying, side-lying with forward knee placement, and side-lying with rearward knee placement), and two camera-to-body distances (35\u2009cm and 50\u2009cm from the PSIS). The cooling\/imaging procedure was repeated using the alternate camera, and data were analyzed using mixed-methods model.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n Temperature change was effectively detected across all skin tones, with cooling resulting in a \u22123.7\u2009\u00b1\u20091.2\u00b0C difference between the region of interest (ROI) and control region. Camera type significantly affected measurements, with the ONE Pro recording 1.04\u00b0C less cooling than the E8-XT. Distance had minimal impact (0.11\u00b0C cooler at 50\u2009cm vs 35\u2009cm at baseline), with no significant difference when comparing ROI to control regions, while lighting and posture had no impact on measurements. Skin tone varied by cooling measurement, with higher melanin levels showing greater temperature changes. A 0.98\u00b0C difference was observed between the lightest and darkest skin tone groups.<\/jats:p>\n <\/jats:sec>\n \n Discussion<\/jats:title>\n Our findings confirm thermal imaging\u2019s robustness across varied environments, with the minor distance effects mitigated through perpendicular measurements and relative temperature comparisons. Significant discrepancies between thermal cameras (>1\u00b0C) highlight that these technologies cannot be used interchangeably when establishing thresholds. While effective across all skin tones, the observed differences in cooling response suggest tailored thresholds may be necessary for darker skin tones. Future research should focus on clinical validation across diverse populations to enhance PrI detection accuracy.<\/jats:p>\n <\/jats:sec>","DOI":"10.1371\/journal.pone.0325091","type":"journal-article","created":{"date-parts":[[2025,9,10]],"date-time":"2025-09-10T17:37:17Z","timestamp":1757525837000},"page":"e0325091","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":6,"title":["Impact of skin tone, environmental, and technical factors on thermal imaging"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9747-5683","authenticated-orcid":true,"given":"Sharon Eve","family":"Sonenblum","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5174-8532","authenticated-orcid":true,"given":"Kathleen","family":"Jordan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Glory Tomi","family":"John","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-0081-3835","authenticated-orcid":true,"given":"Andrew","family":"Chung","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miriam","family":"Asare-Baiden","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9917-5369","authenticated-orcid":true,"given":"Jordan","family":"Pelkmans","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Judy Wawira","family":"Gichoya","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vicki Stover","family":"Hertzberg","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joyce C.","family":"Ho","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2025,9,10]]},"reference":[{"key":"pone.0325091.ref001","unstructured":"European Pressure Ulcer Advisory Panel National Pressure Injury Advisory Panel and Pan Pacific Pressure Injury Alliance. 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