{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T22:27:16Z","timestamp":1789165636730,"version":"build-2803163510"},"reference-count":31,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T00:00:00Z","timestamp":1763683200000},"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>Objective: We assess the prevalence of myopia and its associated factors among schoolchildren in Madrid, Spain, where school-based data using cycloplegic refraction are currently scarce. Methods: A cross-sectional study was conducted in 39 randomly selected schools in Madrid, targeting children in the second (6\u20137 years) and sixth grades (11\u201312 years). Parents completed questionnaires detailing family ocular history, the child\u2019s lifestyle, and screen time. Socio-economic status was inferred from the Human Development Index of school districts. Children were examined using a two-stage approach: initial screening with visual acuity testing and Plusoptix photorefraction (myopia screening cut-off \u2264 0.00 D spherical equivalent), followed by confirmatory cycloplegic autorefraction (three drops of cyclopentolate 1% administered at 10 min intervals), with myopia defined as spherical equivalent \u2264 \u22120.50 D. Statistical analyses included chi-square tests and logistic regression models to evaluate associated factors. Results: Of 3680 children invited, 2489 (67.6%) were examined. Myopia prevalence was 6.5% in second grade and 18.7% in sixth grade. Family history of myopia was a significant risk factor (OR 2.04; 95% CI: 1.53\u20132.70; p &lt; 0.001 for both parents). Outdoor activity during weekends was associated with lower myopia prevalence (OR 0.50; 95% CI: 0.37\u20130.66; p &lt; 0.01 for 2\u20136 h). Screen time was not a significant factor in multivariate analysis. Conclusions: This large school-based study using cycloplegic refraction provides more accurate prevalence data for Spanish schoolchildren. It confirms family history as a major risk factor and highlights the association of outdoor activities with lower prevalence of myopia. These results underline the need for preventive measures and suggest areas for future interventional research.<\/jats:p>","DOI":"10.3390\/ijerph22121766","type":"journal-article","created":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T12:41:58Z","timestamp":1763728918000},"page":"1766","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Prevalence and Risk Factors for Myopia in Primary School Children in Madrid: A School-Based Cycloplegic Refraction Study"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6972-0880","authenticated-orcid":false,"given":"Maria","family":"Nieves-Moreno","sequence":"first","affiliation":[{"name":"Department of Pediatric Ophthalmology, IdiPaz, La Paz Universitary Hospital, 28046 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0054-1731","authenticated-orcid":false,"given":"Gonzalo","family":"Carracedo-Rodriguez","sequence":"additional","affiliation":[{"name":"Ocupharm Research Group, Universidad Complutense de Madrid, 28037 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1546-4807","authenticated-orcid":false,"given":"David Pablo","family":"Pi\u00f1ero-Llorens","sequence":"additional","affiliation":[{"name":"Department of Optics, Pharmacology and Anatomy, University of Alicante, 03690 Alicante, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9753-7696","authenticated-orcid":false,"given":"Laura","family":"Batres Valderas","sequence":"additional","affiliation":[{"name":"Department of Optometry and Vision, Faculty of Optics and Optometry, Complutense University of Madrid, 28037 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9328-9725","authenticated-orcid":false,"given":"Sergio","family":"Recalde-Maestre","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Clinic of Navarra University, 31008 Pamplona, Spain"},{"name":"Retinal Pathologies and New Therapies Group, Experimental Ophthalmology Laboratory, Department of Ophthalmology, Universidad de Navarra, 31008 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Javier","family":"Garc\u00eda-da-Silva","sequence":"additional","affiliation":[{"name":"Association of Magna Myopia with Retinopathies\u2014AMIRES, 28002 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Blanca","family":"D\u00edaz-Vega","sequence":"additional","affiliation":[{"name":"Gran Visi\u00f3n Oftalmolog\u00eda, 28026 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8815-4757","authenticated-orcid":false,"given":"Sara","family":"Llorente-Gonzalez","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Clinic of Navarra University, 31008 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Alarc\u00f3n-Tom\u00e1s","sequence":"additional","affiliation":[{"name":"Puerta de Hierro Universitary Hospital, 28222 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monica","family":"Lovera-Rivas","sequence":"additional","affiliation":[{"name":"Avalens, 28009 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sara","family":"Gutierrez-Jorrin","sequence":"additional","affiliation":[{"name":"OCULUS Iberia SL, 28760 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-6033-1356","authenticated-orcid":false,"given":"Paulina","family":"Dotor-Goytia","sequence":"additional","affiliation":[{"name":"Indizen Optical Technologies S.L., 28002 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3626-6030","authenticated-orcid":false,"given":"Patricia","family":"Fern\u00e1ndez-Robredo","sequence":"additional","affiliation":[{"name":"Retinal Pathologies and New Therapies Group, Experimental Ophthalmology Laboratory, Department of Ophthalmology, Universidad de Navarra, 31008 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pilar","family":"G\u00f3mez de Lia\u00f1o","sequence":"additional","affiliation":[{"name":"General Universitary Hospital Gregorio Mara\u00f1\u00f3n, 28007 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4108-2383","authenticated-orcid":false,"given":"Susana","family":"Noval-Martin","sequence":"additional","affiliation":[{"name":"Department of Pediatric Ophthalmology, IdiPaz, La Paz Universitary Hospital, 28046 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Macarena","family":"Dosal-Franco","sequence":"additional","affiliation":[{"name":"Gran Visi\u00f3n Oftalmolog\u00eda, 28026 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1036","DOI":"10.1016\/j.ophtha.2016.01.006","article-title":"Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 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