{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T19:30:48Z","timestamp":1790796648126,"version":"4.1.0"},"reference-count":53,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2023,3,3]],"date-time":"2023-03-03T00:00:00Z","timestamp":1677801600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"Engineering and Physical Sciences Research Council","doi-asserted-by":"publisher","award":["UCL Small Research Grants Call"],"award-info":[{"award-number":["UCL Small Research Grants Call"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013915","name":"EPSRC Centre for Doctoral Training in Medical Imaging","doi-asserted-by":"publisher","award":["EP\/S021930\/1"],"award-info":[{"award-number":["EP\/S021930\/1"]}],"id":[{"id":"10.13039\/501100013915","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013915","name":"EPSRC Centre for Doctoral Training in Medical Imaging","doi-asserted-by":"publisher","award":["EP\/L016478\/1"],"award-info":[{"award-number":["EP\/L016478\/1"]}],"id":[{"id":"10.13039\/501100013915","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013915","name":"EPSRC Centre for Doctoral Training in Medical Imaging","doi-asserted-by":"publisher","award":["EP\/L016478\/1"],"award-info":[{"award-number":["EP\/L016478\/1"]}],"id":[{"id":"10.13039\/501100013915","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\"><jats:title>Background<\/jats:title><jats:p>Anaemia affects approximately a quarter of the global population. When anaemia occurs during childhood, it can increase susceptibility to infectious diseases and impair cognitive development. This research uses smartphone-based colorimetry to develop a non-invasive technique for screening for anaemia in a previously understudied population of infants and young children in Ghana.<\/jats:p><\/jats:sec><jats:sec id=\"sec002\"><jats:title>Methods<\/jats:title><jats:p>We propose a colorimetric algorithm for screening for anaemia which uses a novel combination of three regions of interest: the lower eyelid (palpebral conjunctiva), the sclera, and the mucosal membrane adjacent to the lower lip. These regions are chosen to have minimal skin pigmentation occluding the blood chromaticity. As part of the algorithm development, different methods were compared for (1) accounting for varying ambient lighting, and (2) choosing a chromaticity metric for each region of interest. In comparison to some prior work, no specialist hardware (such as a colour reference card) is required for image acquisition.<\/jats:p><\/jats:sec><jats:sec id=\"sec003\"><jats:title>Results<\/jats:title><jats:p>Sixty-two patients under 4 years of age were recruited as a convenience clinical sample in Korle Bu Teaching Hospital, Ghana. Forty-three of these had quality images for all regions of interest. Using a na\u00efve Bayes classifier, this method was capable of screening for anaemia (&lt;11.0g\/dL haemoglobin concentration) vs healthy blood haemoglobin concentration (\u226511.0g\/dL) with a sensitivity of 92.9% (95% CI 66.1% to 99.8%), a specificity of 89.7% (72.7% to 97.8%) when acting on unseen data, using only an affordable smartphone and no additional hardware.<\/jats:p><\/jats:sec><jats:sec id=\"sec004\"><jats:title>Conclusion<\/jats:title><jats:p>These results add to the body of evidence suggesting that smartphone colorimetry is likely to be a useful tool for making anaemia screening more widely available. However, there remains no consensus on the optimal method for image preprocessing or feature extraction, especially across diverse patient populations.<\/jats:p><\/jats:sec>","DOI":"10.1371\/journal.pone.0281736","type":"journal-article","created":{"date-parts":[[2023,3,3]],"date-time":"2023-03-03T18:22:11Z","timestamp":1677867731000},"page":"e0281736","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":16,"title":["Feasibility of smartphone colorimetry of the face as an anaemia screening tool for infants and young children in Ghana"],"prefix":"10.1371","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9762-5407","authenticated-orcid":true,"given":"Thomas Alan","family":"Wemyss","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miranda","family":"Nixon-Hill","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Felix","family":"Outlaw","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita","family":"Karsa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Judith","family":"Meek","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christabel","family":"Enweronu-Laryea","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Terence S.","family":"Leung","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2023,3,3]]},"reference":[{"key":"pone.0281736.ref001","unstructured":"Murray C., Lopez A. & Others The global burden of disease: a comprehensive assessment of mortality and disability from diseases, injuries, and risk factors in 1990 and projected to 2020: summary. 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