{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T19:24:20Z","timestamp":1777058660858,"version":"3.51.4"},"reference-count":65,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,5,16]],"date-time":"2022-05-16T00:00:00Z","timestamp":1652659200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004960","name":"Universidad Aut\u00f3noma del Estado de M\u00e9xico","doi-asserted-by":"publisher","award":["6210\/2020CIB"],"award-info":[{"award-number":["6210\/2020CIB"]}],"id":[{"id":"10.13039\/501100004960","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Stress has become a common condition and is one of the chief causes of university course disenrollment. Most of the studies and tests on academic stress have been conducted in research labs or controlled environments, but these tests can not be extended to a real academic environment due to their complexity. Academic stress presents different associated symptoms, anxiety being one of the most common. This study focuses on anxiety derived from academic activities. This study aims to validate the following hypothesis: by using a non-contact method based on the use of remote photoplethysmography (rPPG), it is possible to identify academic stress levels with an accuracy greater than or equal to that of previous works which used contact methods. rPPG signals from 56 first-year engineering undergraduate students were recorded during an experimental task. The results show that the rPPG signals combined with students\u2019 demographic data and psychological scales (the State\u2013Trait Anxiety Inventory) improve the accuracy of different classification methods. Moreover, the results demonstrate that the proposed method provides 96% accuracy by using K-nearest neighbors, J48, and random forest classifiers. The performance metrics show better or equal accuracy compared to other contact methods. In general, this study demonstrates that it is possible to implement a low-cost method for identifying academic stress levels in educational environments.<\/jats:p>","DOI":"10.3390\/s22103780","type":"journal-article","created":{"date-parts":[[2022,5,16]],"date-time":"2022-05-16T21:36:06Z","timestamp":1652736966000},"page":"3780","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Towards a Non-Contact Method for Identifying Stress Using Remote Photoplethysmography in Academic Environments"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6879-0024","authenticated-orcid":false,"given":"Hector Manuel","family":"Morales-Fajardo","sequence":"first","affiliation":[{"name":"School of Engineering, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50100, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0289-7061","authenticated-orcid":false,"given":"Jorge","family":"Rodr\u00edguez-Arce","sequence":"additional","affiliation":[{"name":"School of Engineering, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50100, Mexico"},{"name":"School of Medicine, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50180, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alejandro","family":"Guti\u00e9rrez-Cede\u00f1o","sequence":"additional","affiliation":[{"name":"School of Behavioral Sciences, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9 Caballero","family":"Vi\u00f1as","sequence":"additional","affiliation":[{"name":"School of Engineering, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50100, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5361-5007","authenticated-orcid":false,"given":"Jos\u00e9 Javier","family":"Reyes-Lagos","sequence":"additional","affiliation":[{"name":"School of Medicine, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50180, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eric Alonso","family":"Abarca-Castro","sequence":"additional","affiliation":[{"name":"Divisi\u00f3n de Ciencias Biol\u00f3gicas y de la Salud (Health and Biological Sciences Division), Universidad Aut\u00f3noma Metropolitana, Lerma de Villada 52006, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claudia Ivette","family":"Ledesma-Ram\u00edrez","sequence":"additional","affiliation":[{"name":"School of Medicine, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50180, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5422-5593","authenticated-orcid":false,"given":"Adriana H.","family":"Vilchis-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"School of Engineering, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50100, Mexico"},{"name":"School of Medicine, Universidad Aut\u00f3noma del Estado de M\u00e9xico, Toluca de Lerdo 50180, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1016\/j.rmclc.2015.02.003","article-title":"El estr\u00e9s escolar","volume":"26","author":"Maturana","year":"2015","journal-title":"Revista M\u00e9dica Cl\u00ednica Las Condes"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1002\/smi.2460060310","article-title":"Stress and anxiety: Conceptual and assessment issues","volume":"6","author":"Endler","year":"1990","journal-title":"Stress Med."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Monat, A., and Lazarus, R.S. 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