{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T21:22:03Z","timestamp":1789680123568,"version":"4.0.1"},"reference-count":38,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,5,20]],"date-time":"2021-05-20T00:00:00Z","timestamp":1621468800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,5,20]],"date-time":"2021-05-20T00:00:00Z","timestamp":1621468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Ophthalmol"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Refractive errors and visual impairment in southernmost China have not been reported previously. We aim to investigate and determine the age-specific prevalence of myopia, hyperopia, astigmatism, and visual impairment based on a large population cross-sectional study in Hainan area of southernmost tropical province in China.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A population-based sample of 31,524 children aged 6\u201315\u00a0years from Hainan was assessed. Non-cycloplegic autorefraction and visual acuity (VA) analyses were performed on all participants and a subgroup of participants undergoing cycloplegia.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Of all participants, 23.0% presented uncorrected VA (UCVA) was worse than 20\/40 in worse eye, 6.0% presented mild presenting visual acuity impairment (PVAI), 7.0% presented moderate PVAI, 0.2% presented severe PVAI in the better eye, and 46.9% presented abnormal UCVA [worse than 20\/25 (\u2265\u20096,\u2009&lt;\u20098\u00a0years old) and worse than 20\/20 (\u2265\u20098\u00a0years and older)] at least in one eye. The overall prevalence of myopia [spherical equivalent (SE)\u2009\u2264\u2009\u2009\u2212\u20090.50 D] and high myopia (SE\u2009\u2264\u2009\u2009\u2212\u20096.00 D) were 46.0%, 1.0% respectively. Hyperopia [SE\u2009\u2265\u2009\u2009+\u20091.00 D (\u2265\u20097\u00a0years old) and SE\u2009\u2265\u2009\u2009+\u20092.00 D (\u2265\u20096,\u2009&lt;\u20097\u00a0years old)] and significant hyperopia (SE\u2009\u2265\u2009\u2009+\u20093.00 D) were 4.2 and 0.6%, respectively. Astigmatism [cylinder\u2009\u2265\u20091.00 D (\u2265\u20097\u00a0years old) and\u2009\u2265\u20091.75 D (\u2265\u20096,\u2009&lt;\u20097\u00a0years old)] was found in 31.9%.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Myopia was the most common refractive error in southernmost province in China (Hainan). Its prevalence increased with age, while hyperopia prevalence showed a decreasing trend. However, myopia, especially high myopia prevalence was much lower than in other urban regions across China.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12886-021-01993-5","type":"journal-article","created":{"date-parts":[[2021,5,20]],"date-time":"2021-05-20T18:02:15Z","timestamp":1621533735000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Refractive errors and visual impairment among children and adolescents in southernmost China"],"prefix":"10.1186","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1360-1070","authenticated-orcid":false,"given":"Li","family":"Peng","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ling","family":"Gao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunyan","family":"Zheng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanan","family":"Dai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4984-5584","authenticated-orcid":false,"given":"Qing","family":"Xie","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,5,20]]},"reference":[{"issue":"7","key":"1993_CR1","doi-asserted-by":"publisher","first-page":"855","DOI":"10.1136\/bjophthalmol-2017-311266","volume":"102","author":"TR Fricke","year":"2018","unstructured":"Fricke TR, Jong M, Naidoo KS, Sankaridurg P, Naduvilath TJ, Ho SM, Wong TY, Resnikoff S. 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