{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T14:39:11Z","timestamp":1792593551082,"version":"4.5.0"},"reference-count":54,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,3,28]],"date-time":"2022-03-28T00:00:00Z","timestamp":1648425600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>During the COVID-19 pandemic, computer vision syndrome (CVS) related to online classrooms were unavoidable. This cross-sectional study aimed to explore the prevalence, characteristics and associated factors of CVS. A total of 527 students who were currently studying in a virtual classroom (70.40% female, mean (standard deviation; SD) age of 20.04 (2.17) years) were included. The prevalence of CVS assessed by an online CVS-Questionnaire was 81.0% (427\/527). Comparing with those in the period before the online study, an increase in screen time (interquartile range) in students with and without CVS was 3 (0\u20133) and 2 (1\u20135) h, respectively. Overall, 516 students (97.9%) experienced at least one symptom. The most frequent symptom in CVS subjects was eye pain (96.5%). The most intense symptoms were the feeling of worsening eyesight (15.9%). The factors associated with CVS were female (p &lt; 0.001), age (p = 0.010), atopic diseases (p = 0.020), prior ocular symptoms (p &lt; 0.001), astigmatism (p = 0.033), distance from display &lt;20 cm (p = 0.023), presence of glare or reflection on screen (p &lt; 0.001), low screen brightness (p = 0.045), sleep duration (p = 0.030), inadequate break time between classes (p &lt; 0.001) and increased screen time usage during online study (p &lt; 0.001). Recommendations to prevent CVS based on the adjustable factors might reduce the burden of online study.<\/jats:p>","DOI":"10.3390\/ijerph19073996","type":"journal-article","created":{"date-parts":[[2022,3,29]],"date-time":"2022-03-29T21:44:52Z","timestamp":1648590292000},"page":"3996","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["Self-Reported Computer Vision Syndrome among Thai University Students in Virtual Classrooms during the COVID-19 Pandemic: Prevalence and Associated Factors"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4657-4515","authenticated-orcid":false,"given":"Kampanat","family":"Wangsan","sequence":"first","affiliation":[{"name":"Department of Community Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8590-8568","authenticated-orcid":false,"given":"Phit","family":"Upaphong","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3929-5585","authenticated-orcid":false,"given":"Pheerasak","family":"Assavanopakun","sequence":"additional","affiliation":[{"name":"Department of Community Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0379-2798","authenticated-orcid":false,"given":"Ratana","family":"Sapbamrer","sequence":"additional","affiliation":[{"name":"Department of Community Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9183-4582","authenticated-orcid":false,"given":"Wachiranun","family":"Sirikul","sequence":"additional","affiliation":[{"name":"Department of Community Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amornphat","family":"Kitro","sequence":"additional","affiliation":[{"name":"Department of Community Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naphasorn","family":"Sirimaharaj","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sawita","family":"Kuanprasert","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maneekarn","family":"Saenpo","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suchada","family":"Saetiao","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thitichaya","family":"Khamphichai","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,28]]},"reference":[{"key":"ref_1","unstructured":"(2021, October 17). 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