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Lingham G, Loughman J, Panah DS, Harrington S, Saunders KJ, Ying GS, Cui H, Kobia-Acquah E, Flitcroft DI. The long and short of it: a comprehensive assessment of axial length estimation in myopic eyes from ocular and demographic variables. Eye (Lond) 2024; 38:1333-1341. [PMID: 38200321 PMCID: PMC11076636 DOI: 10.1038/s41433-023-02899-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 01/12/2024] Open
Abstract
BACKGROUND/OBJECTIVES Axial length, a key measurement in myopia management, is not accessible in many settings. We aimed to develop and assess machine learning models to estimate the axial length of young myopic eyes. SUBJECTS/METHODS Linear regression, symbolic regression, gradient boosting and multilayer perceptron models were developed using age, sex, cycloplegic spherical equivalent refraction (SER) and corneal curvature. Training data were from 8135 (28% myopic) children and adolescents from Ireland, Northern Ireland and China. Model performance was tested on an additional 300 myopic individuals using traditional metrics alongside the estimated axial length vs age relationship. Linear regression and receiver operator characteristics (ROC) curves were used for statistical analysis. The contribution of the effective crystalline lens power to error in axial length estimation was calculated to define the latter's physiological limits. RESULTS Axial length estimation models were applicable across all testing regions (p ≥ 0.96 for training by testing region interaction). The linear regression model performed best based on agreement metrics (mean absolute error [MAE] = 0.31 mm, coefficient of repeatability = 0.79 mm) and a smooth, monotonic estimated axial length vs age relationship. This model was better at identifying high-risk eyes (axial length >98th centile) than SER alone (area under the curve 0.89 vs 0.79, respectively). Without knowing lens power, the calculated limits of axial length estimation were 0.30 mm for MAE and 0.75 mm for coefficient of repeatability. CONCLUSIONS In myopic eyes, we demonstrated superior axial length estimation with a linear regression model utilising age, sex and refractive metrics and showed its clinical utility as a risk stratification tool.
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Affiliation(s)
- Gareth Lingham
- Centre for Eye Research Ireland, Environmental Sustainability & Health Institute, Technological University Dublin, Dublin, Ireland
- Ocumetra Ltd., Dublin, Ireland
- Centre for Ophthalmology and Visual Science (incorporating the Lions Eye Institute), the University of Western Australia, Perth, WA, Australia
| | - James Loughman
- Centre for Eye Research Ireland, Environmental Sustainability & Health Institute, Technological University Dublin, Dublin, Ireland
- Ocumetra Ltd., Dublin, Ireland
| | - Davoud Shariat Panah
- Ocumetra Ltd., Dublin, Ireland
- School of Computer Science, Technological University Dublin, Dublin, Ireland
| | - Siofra Harrington
- Centre for Eye Research Ireland, Environmental Sustainability & Health Institute, Technological University Dublin, Dublin, Ireland
- School of Physics and Clinical and Optometric Sciences, Technological University Dublin, Dublin, Ireland
| | - Kathryn J Saunders
- Centre for Optometry and Vision Science, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland
| | - Gui-Shuang Ying
- Center for Preventive Ophthalmology and Biostatistics, Department of Ophthalmology, University of Pennsylvania Perelman School of Medicine, Philadelphia, USA
| | - Hongguang Cui
- The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China
| | - Emmanuel Kobia-Acquah
- Centre for Eye Research Ireland, Environmental Sustainability & Health Institute, Technological University Dublin, Dublin, Ireland
| | - Daniel Ian Flitcroft
- Centre for Eye Research Ireland, Environmental Sustainability & Health Institute, Technological University Dublin, Dublin, Ireland.
- Ocumetra Ltd., Dublin, Ireland.
- Department of Ophthalmology, Children's Health Ireland at Temple Street Hospital, Dublin, Ireland.
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Li DL, Yin ZJ, Li YZ, Zheng YJ, Qin Y, Liang G, Pan CW. Identification of high-risk patterns of myopia in Chinese students based on four major behavioral risk factors: a latent class analysis. BMC Public Health 2023; 23:1378. [PMID: 37464325 DOI: 10.1186/s12889-023-15963-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 05/23/2023] [Indexed: 07/20/2023] Open
Abstract
BACKGROUND Myopia is prevalent in children and adolescents. Understanding the effect of multiple behaviors and their latent patterns on ocular biometric parameters may help clinicians and public health practitioners understand the behavioral risk pattern of myopia from a person-centered perspective. The purpose of this study was to identify the patterns of four major behavioral risk factors associated with myopia, including time spent outdoors, digital screen time, sleep duration, and performance of Chinese eye exercises. The study also examined the relationships between these behavioral patterns and myopia as well as ocular biometric parameters in a sample of Chinese college students. METHODS This study included 2014 students from the Dali University Students Eye Health Study. The average age of the subjects was 19.0 ± 0.9 years old, ranging from 15.7 to 25.1 years old. Each participant's refractive status was measured using an autorefractor without cycloplegia and ocular biometric parameters were measured using an IOL Master. Behavioral risk factors were collected using a pre-designed self-administered questionnaire. Latent class analysis (LCA) was performed to identify cluster patterns of various behaviors. RESULTS The prevalence of myopia was 91.8% in this population. The 2-class model was selected for the LCA based on goodness-of-fit evaluation metrics. Among the overall study sample, 41.1% and 58.9% were assigned into the high-risk and low-risk class, respectively. The risk of myopia [odds ratio (OR) = 2.12, 95% confidence interval (CI) = 1.52-3.14], high myopia (OR = 1.43, 95% CI = 1.14-1.78) and axial length/corneal radius (AL/CR) ratio of more than 3.0 (OR = 1.82, 95% CI = 1.22-2.72) were significantly higher in the high-risk compared with low-risk class. CONCLUSIONS Chinese university students showed differential risks of myopia and could be subdivided into high- and low-risk clusters based on four behavioral variables.
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Affiliation(s)
- Dan-Lin Li
- School of Public Health, Suzhou Medical College of Soochow University, 199 Ren Ai Road, Suzhou, 215123, China
| | - Zhi-Jian Yin
- Department of Ophthalmology, the First Affiliated Hospital of Dali University, Dali, China
| | - Yue-Zu Li
- Department of Ophthalmology, the Affiliated Hospital of Yunnan University, Kunming, China
- Department of Ophthalmology, the Second People's Hospital of Yunnan Province, Kunming, China
| | - Ya-Jie Zheng
- Department of Ophthalmology, the Affiliated Hospital of Yunnan University, Kunming, China
- Department of Ophthalmology, the Second People's Hospital of Yunnan Province, Kunming, China
| | - Yu Qin
- Department of Ophthalmology, the Affiliated Hospital of Yunnan University, Kunming, China
- Department of Ophthalmology, the Second People's Hospital of Yunnan Province, Kunming, China
| | - Gang Liang
- Department of Ophthalmology, the Affiliated Hospital of Yunnan University, Kunming, China.
- Department of Ophthalmology, the Second People's Hospital of Yunnan Province, Kunming, China.
| | - Chen-Wei Pan
- School of Public Health, Suzhou Medical College of Soochow University, 199 Ren Ai Road, Suzhou, 215123, China.
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Harrington S, O'Dwyer V. The association between time spent on screens and reading with myopia, premyopia and ocular biometric and anthropometric measures in 6- to 7-year-old schoolchildren in Ireland. Ophthalmic Physiol Opt 2023; 43:505-516. [PMID: 36843144 DOI: 10.1111/opo.13116] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 01/30/2023] [Accepted: 02/09/2023] [Indexed: 02/28/2023]
Abstract
PURPOSE More time spent on near tasks has consistently been associated with the promotion of myopia. The World Health Organization advises limiting daily screentime to less than 2 h for children aged five and over. This study explored the relationship between time spent on screens and reading/writing with refractive status, ocular biometric and anthropometric factors in 6- to 7-year-olds in Ireland. METHODS Participants were 723 schoolchildren (377 boys [51.8%]), mean age 7.08 (0.45) years. The examination included cycloplegic autorefraction (1% cyclopentolate hydrochloride), ocular biometry (Zeiss IOLMaster), height (cm) and weight (kg). Screentime and reading/writing time were reported by parents/legal guardians by questionnaire. Myopia (≤-0.50D) and premyopia (>-0.50D ≤ 0.75D) risk assessments were performed using logistic regression, and multivariate linear regression was used to analyse continuous variables. RESULTS Reported daily screentimes were 31% <1 h, 49.5% 1-2 h, 15.6% 2-4 h and 3.9% >4 h. Reading/writing times were 42.2% frequently, 48.0% infrequently and 9.8% seldom/never. Linear regression, controlling for age and ethnicity, revealed >2 h/day on screens was associated with a more myopic spherical equivalent [β = -1.15 (95% confidence intervals {CIs}: 1.62-0.69, p < 0.001)], increased refractive astigmatism (β = 0.29, CI: 0.06-0.51, p = 0.01), shorter corneal radius (β = 0.12, CI: 0.02-0.22, p = 0.02), higher axial length/corneal radius (β = 0.06, CI: 0.03-0.09, p < 0.001), heavier weight (β = 1.60, CI: 0.76-2.45, p < 0.001) and higher body mass index (BMI) (β = 1.10, CI: 0.28-1.12, p < 0.001). Logistic regression, controlling for age and ethnicity, revealed daily screentime >2 h was associated with myopia (OR = 10.9, CI: 4.4-27.2, p = 0.01) and premyopia (OR = 2.4, CI: 1.5-3.7, p < 0.001). Frequent reading/writing was associated with screentime ≤2 h/day (OR = 3.2, CI: 1.8-5.8, p < 0.001). CONCLUSION Increased screentime was associated with a more myopic refraction, higher axial length/corneal radius ratio, increased odds of myopia, premyopia, higher degrees of astigmatism, increased weight, BMI and decreased reading/writing time. Dedicated education programmes promoting decreased screentime in children are vital to prevent myopia and support eye and general health.
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Affiliation(s)
- Síofra Harrington
- School of Physics, Clinical, and Optometric Sciences, and Centre for Eye Research Ireland, Technological University Dublin, Dublin, Ireland
| | - Veronica O'Dwyer
- School of Physics, Clinical, and Optometric Sciences, and Centre for Eye Research Ireland, Technological University Dublin, Dublin, Ireland
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Wang J, Han Y, Musch DC, Li Y, Wei N, Qi X, Ding G, Li X, Li J, Song L, Zhang Y, Ning Y, Zeng X, Li Y, Sun L, Hua N, Li S, Jardines S, Qian X. Evaluation and Follow-up of Myopia Prevalence Among School-Aged Children Subsequent to the COVID-19 Home Confinement in Feicheng, China. JAMA Ophthalmol 2023; 141:333-340. [PMID: 36821130 PMCID: PMC9951104 DOI: 10.1001/jamaophthalmol.2022.6506] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Importance Progression of myopia in a school-aged population due to home confinement (January to May 2021) during the COVID-19 pandemic has been previously reported. A key remaining question was whether the myopia spike in children aged 6 to 8 years persisted. Objective To investigate the changes in refractive status and prevalence of myopia in school-aged children 1 year after home confinement ended in China. Design, Setting, and Participants This cross-sectional study with a cohort substudy prospectively evaluated data from school-based photoscreening in Feicheng, China. Children aged 6 to 13 years participated in 8 screenings from 2015 to 2021. Exposures Noncycloplegic photorefraction was conducted using the Spot Vision photoscreener. Main Outcomes and Measures The main outcomes were the differences in spherical equivalent refraction (SER) and prevalence of myopia between 2020 (during home confinement) and 2021 (after home confinement). The SER was recorded for each child, and the prevalence of myopia was calculated annually for each age group. Results A total of 325 443 children participated in the study (51.4% boys, 48.6% girls; age range, 6 to 13 years). Compared with 2020, the mean SER of children in 2021 increased significantly for those aged 6 (0.42 diopters [D]), 7 (0.41 D), and 8 (0.33 D) years. The prevalence of myopia in 2021 was similar to in 2019 for each age group (aged 6 years: 7.9% vs 5.7%; aged 7 years: 13.9% vs 13.6%; aged 8 years: 29.5% vs 26.2%). Both the prevalence of myopia and mean SER for these children returned to their prepandemic levels. Conclusions and Relevance Compared with 2020, the prevalence of myopia among children aged 6 to 8 years in the 2021 screenings decreased, and the mean SER returned to prepandemic level. The refractive development in children aged 6 to 8 years may be most susceptible to environmental changes. These findings support the premise that age 6 to 8 years is a critical period for myopia development and suggest a need to focus preventive interventions for myopia control on children in this age range.
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Affiliation(s)
- Jiaxing Wang
- Department of Ophthalmology, Emory University, Atlanta, Georgia
| | - Yujie Han
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of the National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, China
| | - David C. Musch
- Departments of Ophthalmology and Visual Sciences and Epidemiology, University of Michigan, Ann Arbor, Michigan
| | - Ying Li
- Department of Ophthalmology, Emory University, Atlanta, Georgia
| | - Nan Wei
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Xiaoli Qi
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Gang Ding
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Xue Li
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Jing Li
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Linlin Song
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Ying Zhang
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Yuxian Ning
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Xiaoyu Zeng
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Yaoling Li
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Ling Sun
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of the National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Ning Hua
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Shuo Li
- Department of Respiratory and Critical Medicine, Tianjin Medical University General Hospital, Tianjin, China
| | - Sandra Jardines
- Department of Ophthalmology, Emory University, Atlanta, Georgia
| | - Xuehan Qian
- Department of Strabismus and Pediatric Ophthalmology, Tianjin Medical University Eye Hospital, Tianjin, China
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Gopalakrishnan A, Hussaindeen JR, Chaudhary R, Ramakrishnan B, Arunachalam S, Balakrishnan AC, Sri J S D, Sahoo M, S R, M V, S V, Narayanan A. Results of the School Children Ocular Biometry and Refractive Error Study in South India. Turk J Ophthalmol 2022; 52:412-420. [PMID: 36578223 PMCID: PMC9811226 DOI: 10.4274/tjo.galenos.2021.90008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Objectives Axial length (AL) is an important contributor to refraction, and growth curves are gaining importance in the prediction of myopia. This study aimed to profile the distribution of ocular biometry parameters and to identify correlates of spherical equivalent refraction (SE) among school children in South India. Materials and Methods The School Children Ocular Biometry and Refractive Error study was conducted as part of a school screening program in southern India. The enrolled children underwent tests that included vison check, refraction, binocular vision assessment, and biometry measurements. Results The study included 1382 children whose mean (standard deviation [SD]) age was 10.18 (2.88) years (range: 5-16 years). The sample was divided into 4 groups (grades 1-2, grades 3-5, grades 6-9, and grade 10) based on significant differences in right AL (p<0.001). The mean (SD) AL (range: 20.33-27.27 mm) among the four groups was 22.50 (0.64) mm, 22.88 (0.69) mm, 23.30 (0.82) mm, and 23.58 (0.87) mm, respectively. The mean SE (range: +1.86 to -6.56 D) was 0.08 (0.65 D) in class 1 and decreased with increasing grade to -0.39 (1.20 D) in grade 10. There was a significant difference in all biometry parameters between boys and girls (p<0.001). Age, AL, and mean corneal curvature were the main predictors of SE. Conclusion This study provides a profile of ocular biometry parameters among school children in South India for comparison against profiles from other regions across the country. The study data will form a reference for future studies assessing myopia in this ethnicity.
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Affiliation(s)
- Aparna Gopalakrishnan
- *Srimathi Sundari Subramanian Department of Visual Psychophysics, Unit of Medical Research Foundation, Myopia Clinic, Chennai, India
| | - Jameel Rizwana Hussaindeen
- *Srimathi Sundari Subramanian Department of Visual Psychophysics, Unit of Medical Research Foundation, Myopia Clinic, Chennai, India,* Address for Correspondence: Srimathi Sundari Subramanian Department of Visual Psychophysics, Unit of Medical Research Foundation, Myopia Clinic, Chennai, India E-mail:
| | - Romans Chaudhary
- The Sankara Nethralaya Academy, Unit of Medical Research Foundation, Chennai, India
| | - Bhavatharini Ramakrishnan
- *Srimathi Sundari Subramanian Department of Visual Psychophysics, Unit of Medical Research Foundation, Myopia Clinic, Chennai, India
| | - Sushil Arunachalam
- *Srimathi Sundari Subramanian Department of Visual Psychophysics, Unit of Medical Research Foundation, Myopia Clinic, Chennai, India
| | | | - Deepika Sri J S
- Elite School of Optometry, Unit of Medical Research Foundation, Chennai, India
| | - Manaswini Sahoo
- Elite School of Optometry, Unit of Medical Research Foundation, Chennai, India
| | - Robin S
- Elite School of Optometry, Unit of Medical Research Foundation, Chennai, India
| | - Varsaharinya M
- Elite School of Optometry, Unit of Medical Research Foundation, Chennai, India
| | - Vishnupriya S
- Elite School of Optometry, Unit of Medical Research Foundation, Chennai, India
| | - Anuradha Narayanan
- Elite School of Optometry, Unit of Medical Research Foundation, Chennai, India
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Association of Axial Length and Refraction with Near Horizontal Heterophoria in Chinese Children: An Observational Cross-Sectional Study. J Ophthalmol 2022; 2022:7549851. [PMID: 35685903 PMCID: PMC9173904 DOI: 10.1155/2022/7549851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 05/15/2022] [Accepted: 05/16/2022] [Indexed: 11/17/2022] Open
Abstract
Purpose To evaluate the association of near heterophoria with refraction and axial length (AL) in Chinese school children. Methods This school-based cross-sectional study included 15,081 Chinese primary school children (grades 1–6) examined during 2017. Near heterophoria was measured at 33 cm using the Maddox rod and prism test. Noncycloplegic refraction and AL were also measured. A generalized additive model with a Gaussian link was used to determine the association of near heterophoria with refraction and AL. Analyses were adjusted for age to account for differences in the age distribution of the sample. Results Overall, data were analyzed for 11,013 students ranging in age from 6 to 13 years. The most common type of near heterophoria was exophoria (64.96%), the proportion and value of which increased according to grade. Exophoria accounted for 62.53% (2,328/3,723), 65.03% (2,501/3,846), and 67.51% (2,325/3,444) of near heterophoria cases for grades 1-2, grades 3-4, and grades 5-6, respectively. Prism diopter (PD) values for near heterophoria in these grades were −6.30 ± 3.69, −6.81 ± 4.01, and −8.32 ± 5.12 PD, respectively. The average spherical equivalent (SE) in children with orthophoria was 0.23 D and 0.25 D lower than those in children with exophoria and esophoria, respectively (P < 0.001). The mean AL in children with orthophoria was 0.11 mm shorter than that in children with either exophoria or esophoria (P < 0.001). Near heterophoria exhibited a significant correlation with refraction and AL, irrespective of age. Conclusions Exophoria represents the most common type of near heterophoria in children. Children with more severe near heterophoria, whether exophoria or esophoria, exhibited a higher degree of myopia and longer AL than those with relatively less severe near heterophoria. These results highlight the need for further, long-term investigation regarding the role of near heterophoria in visual development.
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Demir P, Baskaran K, Theagarayan B, Gierow P, Sankaridurg P, Macedo AF. Refractive error, axial length, environmental and hereditary factors associated with myopia in Swedish children. Clin Exp Optom 2021; 104:595-601. [PMID: 33689658 DOI: 10.1080/08164622.2021.1878833] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Clinical relevance: Investigation of refractive errors amongst Swedish schoolchildren will help identify risk factors associated with myopia development.Background: Genetic and hereditary aspects have been linked with the development of myopia. Nevertheless, in the case of 'school myopia' some authors suggest that environmental factors may affect gene expression, causing school myopia to soar. Additional understanding about which environmental factors play a relevant role can be gained by studying refractive errors in countries like Sweden, where prevalence of myopia is expected to be low.Methods: Swedish schoolchildren aged 8-16 years were invited to participate. Participants underwent an eye examination, including cycloplegic refraction and axial length (AL) measurements. Predictors such as time spent in near work, outdoor activities and parental myopia were obtained using a questionnaire. Myopia was defined as spherical equivalent refraction (SER) ≤ -0.50D and hyperopia as SER ≥ +0.75D.Results: A total of 128 children (70 females and 58 males) participated in this study with mean age of 12.0 years (SD = 2.4). Based on cycloplegic SER of the right eye, the distribution of refractive errors was: hyperopia 48.0% (CI95 = 38.8-56.7), emmetropia 42.0% (CI95 = 33.5-51.2) and myopia 10.0%. (CI95 = 4.4-14.9). The mean AL was 23.1 mm (SD = 0.86), there was a correlation between SER and AL, r = -0.65 (p < 0.001). Participants with two myopic parents had higher myopia and increased axial length than those with one or no myopic parents. The mean time spent in near work, outside of school, was 5.3 hours-per-day (SD = 3.1), and mean outdoor time reported was 2.6 hours-per-day (SD = 2.2) for all the participants. The time spent in near work and outdoor time were different for different refractive error categories.Conclusion: The prevalence of myopia amongst Swedish schoolchildren is low. Hereditary and environmental factors are associated with refractive error categories. Further studies with this sample are warranted to investigate how refractive errors and environmental factors interact over time.
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Affiliation(s)
- Pelsin Demir
- Medicine and Optometry, Linnaeus University, Kalmar, Sweden
| | | | | | - Peter Gierow
- Medicine and Optometry, Linnaeus University, Kalmar, Sweden
| | - Padmaja Sankaridurg
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Antonio Filipe Macedo
- Medicine and Optometry, Linnaeus University, Kalmar, Sweden.,Center of Physics - Optometry and Vision Science, University of Minho, Braga, Portugal
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