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ImportanceThe potential association of schizophrenia with distinct retinal changes is of clinical interest but has been challenging to investigate because of a lack of sufficiently large and detailed cohorts.ObjectiveTo investigate the association between retinal biomarkers from multimodal imaging (oculomics) and schizophrenia in a large real-world population.Design, Setting, and ParticipantsThis cross-sectional analysis used data from a retrospective cohort of 154 830 patients 40 years and older from the AlzEye study, which linked ophthalmic data with hospital admission data across England. Patients attended Moorfields Eye Hospital, a secondary care ophthalmic hospital with a principal central site, 4 district hubs, and 5 satellite clinics in and around London, United Kingdom, and had retinal imaging during the study period (January 2008 and April 2018). Data were analyzed from January 2022 to July 2022.Main Outcomes and MeasuresRetinovascular and optic nerve indices were computed from color fundus photography. Macular retinal nerve fiber layer (RNFL) and ganglion cell–inner plexiform layer (mGC-IPL) thicknesses were extracted from optical coherence tomography. Linear mixed-effects models were used to examine the association between schizophrenia and retinal biomarkers.ResultsA total of 485 individuals (747 eyes) with schizophrenia (mean [SD] age, 64.9 years [12.2]; 258 [53.2%] female) and 100 931 individuals (165 400 eyes) without schizophrenia (mean age, 65.9 years [13.7]; 53 253 [52.8%] female) were included after images underwent quality control and potentially confounding conditions were excluded. Individuals with schizophrenia were more likely to have hypertension (407 [83.9%] vs 49 971 [48.0%]) and diabetes (364 [75.1%] vs 28 762 [27.6%]). The schizophrenia group had thinner mGC-IPL (−4.05 μm, 95% CI, −5.40 to −2.69; P = 5.4 × 10−9), which persisted when investigating only patients without diabetes (−3.99 μm; 95% CI, −6.67 to −1.30; P = .004) or just those 55 years and younger (−2.90 μm; 95% CI, −5.55 to −0.24; P = .03). On adjusted analysis, retinal fractal dimension among vascular variables was reduced in individuals with schizophrenia (−0.14 units; 95% CI, −0.22 to −0.05; P = .001), although this was not present when excluding patients with diabetes.Conclusions and RelevanceIn this study, patients with schizophrenia had measurable differences in neural and vascular integrity of the retina. Differences in retinal vasculature were mostly secondary to the higher prevalence of diabetes and hypertension in patients with schizophrenia. The role of retinal features as adjunct outcomes in patients with schizophrenia warrants further investigation.

Contains fulltext : 292919.pdf (Publisher’s version ) (Open Access) BACKGROUND: High myopia (HM), defined as a spherical equivalent refractive error (SER) ≤ -6.00 diopters (D), is a leading cause of sight impairment, through myopic macular degeneration (MMD). We aimed to derive an improved polygenic score (PGS) for predicting children at risk of HM and to test if a PGS is predictive of MMD after accounting for SER. METHODS: The PGS was derived from genome-wide association studies in participants of UK Biobank, CREAM Consortium, and Genetic Epidemiology Research on Adult Health and Aging. MMD severity was quantified by a deep learning algorithm. Prediction of HM was quantified as the area under the receiver operating curve (AUROC). Prediction of severe MMD was assessed by logistic regression. FINDINGS: In independent samples of European, African, South Asian and East Asian ancestry, the PGS explained 19% (95% confidence interval 17-21%), 2% (1-3%), 8% (7-10%) and 6% (3-9%) of the variation in SER, respectively. The AUROC for HM in these samples was 0.78 (0.75-0.81), 0.58 (0.53-0.64), 0.71 (0.69-0.74) and 0.67 (0.62-0.72), respectively. The PGS was not associated with the risk of MMD after accounting for SER: OR = 1.07 (0.92-1.24). INTERPRETATION: Performance of the PGS approached the level required for clinical utility in Europeans but not in other ancestries. A PGS for refractive error was not predictive of MMD risk once SER was accounted for. FUNDING: Supported by the Welsh Government and Fight for Sight (24WG201).

Background/aimsUnderstanding temporal trends in childhood visual disability is necessary for planning and evaluating clinical services and health policies. We investigate the changing epidemiology of severe visual impairment (SVI) and blindness (BL) in children in the UK in the 21st century.MethodsComparative analysis of two national population-based epidemiological studies of incident childhood SVI/BL (ICD-10 definition; visual acuity worse than 1.0 LogMAR in the better eye). We carry out comparative analysis of studies conducted in 2000 and 2015 using identical methods.ResultsOverall annual and cumulative incidence rates remained broadly stable in 2015 at 0.38 per 10 000 (95% CI 0.34 to 0.41) for 0–15 years old and 5.65 per 10 000 (5.16 to 6.18) by 16 years, respectively, and with annual incidence in infancy (3.52 per 10 000, 3.13 to 3.97) remaining considerably higher than any other age. Mortality among children diagnosed in infancy declined (from 61.4 to 25.6 per 1000), despite an increase (from 77% to 84%, p=0.037) in the overall proportion with significant non-ophthalmic impairments/disorders. The relative contribution of all the main groups of disorders increased over time, most notably cerebral visual impairment (from 50% to 61%). Aetiological factors operating prenatally continued to predominate, with an increased relative contribution of hereditary conditions in all children (from 35% to 57%, pConclusionThe changing landscape of healthcare and increased survival of affected children, is reflected in increasing clinical complexity and heterogeneity of all-cause SVI/BL alongside declining mortality.

Purpose: Serum lipids are modifiable, routinely collected blood test features associated with cardiovascular health. We examined the association of commonly collected serum lipid measures (total cholesterol [TC], high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol [LDL-C], and triglycerides) with intraocular pressure (IOP). Design: Cross-sectional study in the UK Biobank and European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk cohorts. Participants: We included 94 323 participants from the UK Biobank (mean age, 57 years) and 6230 participants from the EPIC-Norfolk (mean age, 68 years) cohorts with data on TC, HDL-C, LDL-C, and triglycerides collected between 2006 and 2009. Methods: Multivariate linear regression adjusting for demographic, lifestyle, anthropometric, medical, and ophthalmic covariables was used to examine the associations of serum lipids with corneal-compensated IOP (IOPcc). Main Outcome Measures: Corneal-compensated IOP. Results: Higher levels of TC, HDL-C, and LDL-C were associated independently with higher IOPcc in both cohorts after adjustment for key demographic, medical, and lifestyle factors. For each 1-standard deviation increase in TC, HDL-C, and LDL-C, IOPcc was higher by 0.09 mmHg (95% confidence interval [CI], 0.06–0.11 mmHg; P < 0.001), 0.11 mmHg (95% CI, 0.08–0.13 mmHg; P < 0.001), and 0.07 mmHg (95% CI, 0.05–0.09 mmHg; P < 0.001), respectively, in the UK Biobank cohort. In the EPIC-Norfolk cohort, each 1-standard deviation increase in TC, HDL-C, and LDL-C was associated with a higher IOPcc by 0.19 mmHg (95% CI, 0.07–0.31 mmHg; P = 0.001), 0.14 mmHg (95% CI, 0.03–0.25 mmHg; P = 0.016), and 0.17 mmHg (95% CI, 0.06–0.29 mmHg; P = 0.003). An inverse association between triglyceride levels and IOP in the UK Biobank (–0.05 mmHg; 95% CI, –0.08 to –0.03; P < 0.001) was not replicated in the EPIC-Norfolk cohort (P = 0.30). Conclusions: Our findings suggest that serum TC, HDL-C, and LDL-C are associated positively with IOP in 2 United Kingdom cohorts and that triglyceride levels may be associated negatively. Future research is required to assess whether these associations are causal in nature.

Background/aimsEvaluation of telemedicine care models has highlighted its potential for exacerbating healthcare inequalities. This study seeks to identify and characterise factors associated with non-attendance across face-to-face and telemedicine outpatient appointments.MethodsA retrospective cohort study at a tertiary-level ophthalmic institution in the UK, between 1 January 2019 and 31 October 2021. Logistic regression modelled non-attendance against sociodemographic, clinical and operational exposure variables for all new patient registrations across five delivery modes: asynchronous, synchronous telephone, synchronous audiovisual and face to face prior to the pandemic and face to face during the pandemic.ResultsA total of 85 924 patients (median age 55 years, 54.4% female) were newly registered. Non-attendance differed significantly by delivery mode: (9.0% face to face prepandemic, 10.5% face to face during the pandemic, 11.7% asynchronous and 7.8%, synchronous during pandemic). Male sex, greater levels of deprivation, a previously cancelled appointment and not self-reporting ethnicity were strongly associated with non-attendance across all delivery modes. Individuals identifying as black ethnicity had worse attendance in synchronous audiovisual clinics (adjusted OR 4.24, 95% CI 1.59 to 11.28) but not asynchronous. Those not self-reporting their ethnicity were from more deprived backgrounds, had worse broadband access and had significantly higher non-attendance across all modes (all pConclusionPersistent non-attendance among underserved populations attending telemedicine appointments highlights the challenge digital transformation faces for reducing healthcare inequalities. Implementation of new programmes should be accompanied by investigation into the differential health outcomes of vulnerable populations.

Importance: Uncertainty currently exists about whether the same genetic variants are associated with susceptibility to low myopia (LM) and high myopia (HM) and to myopia and hyperopia. Addressing this question is fundamental to understanding the genetics of refractive error and has clinical relevance for genotype-based prediction of children at risk for HM and for identification of new therapeutic targets. Objective: To assess whether a common set of genetic variants are associated with susceptibility to HM, LM, and hyperopia. Design, Setting, and Participants: This genetic association study assessed unrelated UK Biobank participants 40 to 69 years of age of European and Asian ancestry. Participants 40 to 69 years of age living in the United Kingdom were recruited from January 1, 2006, to October 31, 2010. Of the total sample of 502682 participants, 117279 (23.3%) underwent an ophthalmic assessment. Data analysis was performed from December 12, 2019, to June 23, 2020. Exposures: Four refractive error groups were defined: HM, -6.00 diopters (D) or less; LM, -3.00 to -1.00 D; hyperopia, +2.00 D or greater; and emmetropia, 0.00 to +1.00 D. Four genome-wide association study (GWAS) analyses were performed in participants of European ancestry: (1) HM vs emmetropia, (2) LM vs emmetropia, (3) hyperopia vs emmetropia, and (4) LM vs hyperopia. Polygenic risk scores were generated from GWAS summary statistics, yielding 4 sets of polygenic risk scores. Performance was assessed in independent replication samples of European and Asian ancestry. Main Outcomes and Measures: Odds ratios (ORs) of polygenic risk scores in replication samples. Results: A total of 51841 unrelated individuals of European ancestry and 2165 unrelated individuals of Asian ancestry were assigned to a specific refractive error group and included in our analyses. Polygenic risk scores derived from all 4 GWAS analyses were predictive of all categories of refractive error in both European and Asian replication samples. For example, the polygenic risk score derived from the HM vs emmetropia GWAS was predictive in the European sample of HM vs emmetropia (OR, 1.58; 95% CI, 1.41-1.77; P = 1.54 × 10-15) as well as LM vs emmetropia (OR, 1.15; 95% CI, 1.07-1.23; P = 8.14 × 10-5), hyperopia vs emmetropia (OR, 0.83; 95% CI, 0.77-0.89; P = 4.18 × 10-7), and LM vs hyperopia (OR, 1.45; 95% CI, 1.33-1.59; P = 1.43 × 10-16). Conclusions and Relevance: Genetic risk variants were shared across HM, LM, and hyperopia and across European and Asian samples. Individuals with HM inherited a higher number of variants from among the same set of myopia-predisposing alleles and not different risk alleles compared with individuals with LM. These findings suggest that treatment interventions targeting common genetic risk variants associated with refractive error could be effective against both LM and HM..

BackgroundPatient-reported outcome measures (PROMs) are increasingly used in paediatric ophthalmology. However, little is known about the distribution of PROM scores among children and young people with visual impairment.AimTo investigate the distributions and predictors of scores on the VQoL_CYP (measuring vision-related quality of life) and FVQ_CYP (measuring functional vision).MethodsChildren and young people aged 8–18 years, with visual impairment/blindness (logarithm of the minimum angle of resolution (LogMAR) worse than 0.48 in the better eye, and/or eligible visual field restriction) completed the VQoL_CYP and FVQ_CYP at home or Great Ormond Street Hospital, London, UK. Associations between VQoL_CYP and FVQ_CYP scores and sociodemographic and clinical factors were analysed using multiple linear regression models.ResultsAmong 93 participants, VQoL_CYP scores ranged from 36.6 to 78.2 (mean=57.9, SD=8.1). FVQ_CYP scores ranged from 23.5 to 70.3 (mean=48.3, SD=10.1). Only 0.4% of the variation in VQoL_CYP scores was explained, with no associations with the variables of interest. By contrast, 21.6% of the variation in FVQ_CYP scores was explained, with a gradient of worse acuity (pDiscussionSelf-rated vision-related quality of life and functional vision are not readily predicted from sociodemographic or clinical characteristics that ophthalmologists measure/record. Routine use of PROMs in clinical practice can offer important insights. Use in research can provide valuable measures of effectiveness of interventions. The reference values provided will aid interpretation in both settings.

Summary Background The WHO VISION 2020 global initiative against blindness, launched in 2000, prioritised childhood visual disability by aiming to end avoidable childhood blindness by 2020. However, progress has been hampered by the global paucity of epidemiological data concerning childhood visual disability. The British Childhood Visual Impairment and Blindness Study 2 (BCVIS2) was done to address this evidence gap. Methods BCVIS2 was a prospective UK-wide, cross-sectional, observational study to establish an inception cohort of children newly diagnosed with visual impairment. Ophthalmologists and paediatricians reported cases from 89 hospitals and community centres across the UK. We included children aged 18 years or younger who were newly diagnosed with any condition causing impaired visual acuity to a level of 0·5 logMAR or worse (worse than 6/18 Snellen) in each eye, or equivalent vision as assessed by standard qualitative measures, between Oct 1, 2015, and Nov 1, 2016. Eligible children were notified simultaneously but independently by their managing ophthalmologists and paediatricians via the two national active surveillance schemes, the British Ophthalmological Surveillance Unit and the British Paediatric Surveillance Unit. Standardised detailed demographic, socioeconomic, and clinical data about detection, management, and treatment were collected at diagnosis and 1 year later. We calculated incidence estimates and relative rates by key sociodemographic factors. We did descriptive analyses of underlying ophthalmic disorders and non-ophthalmic comorbidities. Findings 61 (7%) of 845 eligible children initially notified were ineligible at follow-up because of improved vision after treatment. Thus, the study sample comprised 784 children with permanent newly-diagnosed all-cause visual impairment, severe visual impairment, or blindness. 559 (72%) of 778 children had clinically significant non-ophthalmic impairments or conditions. 28 (4%) of 784 children died within a year after diagnosis of visual disability (all had underlying systemic disorders). Incidence of visual disability in the first year of life was 5·19 per 10 000 children (95% CI 4·71–5·72), almost ten times higher than among 1-to-4-year-olds and between 20 times and 100 times higher than in the older age groups. The overall cumulative incidence (or lifetime risk) of visual impairment, severe visual impairment, or blindness was 10·03 per 10 000 children (9·35–10·76). Incidence rates were higher for those from any ethnic minority group, the lowest quintile of socioeconomic status, and those born preterm or with low birthweight. 345 (44%) of 784 children had a single affected anatomical site. Disorders of the brain and visual pathways affected 378 (48%) of 784 children. Interpretation BCVIS2 provides a contemporary snapshot of the heterogeneity, multi-morbidity, and vulnerability associated with childhood visual disability in a high-income country. These findings could facilitate developing and delivering health care and planning of interventional research. Our findings highlight the importance of including childhood visual disability as a sentinel event and metric in global child health initiatives. Funding Fight for Sight, National Institute for Health Research, and Ulverscroft Foundation.

PurposeRetinal signatures of systemic disease (‘oculomics’) are increasingly being revealed through a combination of high-resolution ophthalmic imaging and sophisticated modelling strategies. Progress is currently limited not mainly by technical issues, but by the lack of large labelled datasets, a sine qua non for deep learning. Such data are derived from prospective epidemiological studies, in which retinal imaging is typically unimodal, cross-sectional, of modest number and relates to cohorts, which are not enriched with subpopulations of interest, such as those with systemic disease. We thus linked longitudinal multimodal retinal imaging from routinely collected National Health Service (NHS) data with systemic disease data from hospital admissions using a privacy-by-design third-party linkage approach.ParticipantsBetween 1 January 2008 and 1 April 2018, 353 157 participants aged 40 years or older, who attended Moorfields Eye Hospital NHS Foundation Trust, a tertiary ophthalmic institution incorporating a principal central site, four district hubs and five satellite clinics in and around London, UK serving a catchment population of approximately six million people.Findings to dateAmong the 353 157 individuals, 186 651 had a total of 1 337 711 Hospital Episode Statistics admitted patient care episodes. Systemic diagnoses recorded at these episodes include 12 022 patients with myocardial infarction, 11 735 with all-cause stroke and 13 363 with all-cause dementia. A total of 6 261 931 retinal images of seven different modalities and across three manufacturers were acquired from 1 54 830 patients. The majority of retinal images were retinal photographs (n=1 874 175) followed by optical coherence tomography (n=1 567 358).Future plansAlzEye combines the world’s largest single institution retinal imaging database with nationally collected systemic data to create an exceptional large-scale, enriched cohort that reflects the diversity of the population served. First analyses will address cardiovascular diseases and dementia, with a view to identifying hidden retinal signatures that may lead to earlier detection and risk management of these life-threatening conditions.

Purpose To describe and compare associations with macular retinal nerve fiber layer (mRNFL), ganglion cell complex (GCC), and ganglion cell–inner plexiform layer (GCIPL) thicknesses in a large cohort. Design Cross-sectional study. Participants We included 42 044 participants in the UK Biobank. The mean age was 56 years. Methods Spectral-domain OCT macular images were segmented and analyzed. Corneal-compensated intraocular pressure (IOPcc) was measured with the Ocular Response Analyzer (Reichert, Corp., Buffalo, NY). Multivariable linear regression was used to examine associations with mean mRNFL, GCC, and GCIPL thicknesses. Factors examined were age, sex, ethnicity, height, body mass index (BMI), smoking status, alcohol intake, Townsend deprivation index, education level, diabetes status, spherical equivalent, and IOPcc. Main Outcome Measures Thicknesses of mRNFL, GCC, and GCIPL. Results We identified several novel independent associations with thinner inner retinal thickness. Thinner inner retina was associated with alcohol intake (most significant for GCIPL: –0.46 μm for daily or almost daily intake compared with special occasion only or never [95% confidence interval (CI), 0.61–0.30]; P = 1.1×10–8), greater social deprivation (most significant for GCIPL: –0.28 μm for most deprived quartile compared with least deprived quartile [95% CI, –0.42 to –0.14]; P = 6.6×10–5), lower educational attainment (most significant for mRNFL: –0.36 μm for less than O level compared with degree level [95% CI, –0.45 to 0.26]; P = 2.3×10–14), and nonwhite ethnicity (most significant for mRNFL comparing blacks with whites: –1.65 μm [95% CI, –1.86 to –1.43]; P = 2.4×10–50). Corneal-compensated intraocular pressure was associated most significantly with GCIPL (–0.04 μm/mmHg [95% CI, –0.05 to –0.03]; P = 4.0×10–10) and was not associated significantly with mRNFL (0.00 μm/mmHg [95% CI, –0.01 to 0.01]; P = 0.77). The variables examined explained a greater proportion of the variance of GCIPL (11%) than GCC (6%) or mRNFL (7%). Conclusions The novel associations we identified may be important to consider when using inner retinal parameters as a diagnostic tool. Associations generally were strongest with GCIPL, particularly for IOP. This suggests that GCIPL may be the superior inner retinal biomarker for macular pathophysiologic processes and especially for glaucoma.

Background/aimsTo investigate if impaired vision adversely impacts the intentions/ambitions of adolescents concerning their future education, careers and social outcomes.MethodsPopulation-based birth cohort study in the UK comprising 9273 participants from the Millennium Cohort Study who were followed up to age 17 years. Children were classified as having normal vision or unilateral or bilateral impaired vision caused by significant eye conditions based on detailed parental-structured questionnaire data on sight problems and treatment coded by clinicians. Ten domains covering education, career and social outcomes by age 30 were investigated.ResultsAdjusted regression models showed few differences by vision status. Bilateral impaired vision was associated with increased odds of intending to remain in full-time education after statutory school age (adjusted OR (aOR) 2.00, 95% CI 1.08 to 3.68) and of home ownership at age 30 (aOR 1.83, 95% CI 1.01 to 3.32). Impaired vision was not associated with intending to attend university. A significantly higher proportion of parents of children with bilateral or unilateral impaired vision thought that their child would not get the exam grades required to go to university than parents of those with normal vision (29% or 26% vs 16%,p=0.026).ConclusionAdolescents with impaired vision have broadly the same intentions/ambitions regarding future education, careers and social outcomes as their peers with normal vision. The known significant gaps in attainment in these domains among young adults with vision impairment are therefore likely to be due to barriers that they face in achieving their ambitions. Improved implementation of existing interventions is necessary to ensure equality of opportunities.

Purpose Air pollution is associated with chronic diseases of later life. Cataract is the most common cause of blindess globally. It is biologically plausible that cataract risk is increased by pollution exposure. Therefore, the relationship between air pollution and incident cataract surgery was examined. Methods This was a prospective, observational study involving 433,727 UK Biobank participants. Ambient air pollution measures included particulates, nitrogen dioxide (NO2) and nitrogen oxides (NOx). Outdoor air pollution was estimated based on land use regression models. Participants undergoing cataract surgery in either eye were ascertained via data linkage to the National Health Service procedure statistics. Those undergoing cataract surgery within 1 year of baseline assessment and those reporting cataract at baseline were excluded. Cox proportional hazards models were used to examine the associations between air pollutants and incident cataract surgery, adjusting for sociodemographic and lifestyle factors. Results There were 16,307 incident cases of cataract surgery. Higher exposure to PM2.5 was associated with a 5% increased risk of incident cataract surgery (per interquartile range [IQR] increase). Compared to the lowest quartile, participants with exposures to PM2.5, NO2, and NOx in the highest quartile were 14%, 11%, and 9% more likely to undergo cataract surgery, respectively. A continuous exposure-response relationship was observed, with the likelihood of undergoing cataract surgery being progressively higher with greater levels of PM2.5, NO2, and NOx (P for trend P < 0.001). Conclusions Although the results of our study showed a 5% increased risk of future cataract surgery following an exposure to PM2.5, NO2, and NOx, the effect estimates were relatively small. Further research is required to determine if the associations identified are causal.

BACKGROUND We describe an investigation of temporal trends in the incidence of childhood uveitis-related hospital admissions, hospitalization being a robust indicator of disease severity. METHODS A population-based retrospective study using a hospitalization database, the Hospital Episode Statistics (HES) dataset, capturing data on care between 2013 and 2020. Primary outcomes were rates of pediatric hospital admissions for uveitis-related disorders. RESULTS During the study period, there were 3,258 reported uveitis-related hospital admissions of children aged 0 to 14 years, comprising 19% of all-age uveitis-related admissions. Anterior uveitis was the most common diagnosis. The annual incidence of childhood uveitis-related hospitalizations declined year on year from a peak incidence of 5.4 per 100,000 children (95% confidence interval 5.0-5.9) in 2015-2016 to 3.3 per 100,000 (95% CI 3.0-3.6) in 2019-2020. Over the same period, the national incidence of juvenile arthropathy-related admissions stayed stable. CONCLUSION The decline in admissions nationally may reflect reduced incidence of uveitis complications with increasing use of immunosuppressive therapies.

Purpose:\ud To investigate disagreement between children's self-reported vision-related quality of life (VQoL) and functional vision (FV), and their parents’ proxy-reports.\ud \ud Design:\ud Cross-sectional study.\ud \ud Methods:\ud 152 children aged 7-18 years with visual impairment (VI) (defined by the World Health Organization), and their parents, were recruited from 22 National Health Service (NHS) Ophthalmology Departments in the United Kingdom.\ud \ud Age-appropriate versions of 2 vision-specific instruments capturing VQoL and FV, were administered to children alongside modified versions for completion by parents on behalf of their child (i.e. parent proxy-report). Disagreement between self- and parent proxy-report was examined using the Bland-Altman (BA) method, and a threshold of disagreement based on 0.5 standard deviation. Disagreement was analysed according to participants’ age, gender and clinical characteristics, using logistic regression analyses.\ud \ud Results:\ud Children rated themselves as having better outcomes than their parents did, although parents both under- and over-estimated their child's VQoL (mean score difference = 7.7). With each year of increasing age, there was a 1.18 (1.04 – 1.35) higher odds of children self-rating their VQoL better than their parents (p = 0.013). Although parents consistently under-estimated their child's FV (mean score difference = -4.7), no characteristics were significantly associated with differences in disagreement.\ud \ud Conclusions:\ud Disagreement between child self-report on the impact of VI, and their parents’ proxy-reports varies by age. This implies that self-report from children must remain the gold standard. Where self-reporting is not possible, parent proxy-reports may provide useful insights, but must be interpreted with caution.

Background/aimsAddressing childhood visual disability is an international priority, with data on causes needed to plan, implement and evaluate public health and clinical care. We have examined the contribution of ‘avoidable’ blinding disorders to childhood visual impairment, severe visual impairment and blindness (VI/SVIBL) in the UK.MethodsNational prospective observational longitudinal study, the British Childhood Visual Impairment and Blindness Study 2 (BCVIS2), of children (aged 18 years or under) newly diagnosed with vision worse than 0.48 logMAR (logarithm of the minimum angle of resolution) or equivalent in both eyes. Proportions of children with an ‘avoidable’ disorder comprising either apotentially preventable(isolated disorders with an effective intervention which reduces disease incidence) ortreatable(isolated eye or vision disorders for which there are routinely available effective interventions able to improve vision or halt progressive visual loss) are reported.ResultsOf the 784 children within BCVIS2, isolated potentially preventable disorders were present in only 17% (132/784) and treatable disorders in an additional 13% (99/784). The most common treatable causes were cataract, retinopathy of prematurity and glaucoma. Of the 132 children with potentially preventable disease, 64 had hypoxic–ischaemic encephalopathy. Non-accidental injury accounted for almost two-thirds (11/16, 69%) of those with VI/SVIBL due to injury.ConclusionDespite significant progress in the past decades in high-income countries, there remains a need to be vigilant about implementing preventive strategies and treatments. Attention to disorders that are currently neither preventable nor treatable remains a priority in these settings and will become increasingly important in lower-income and middle-income countries undergoing economic transition.

Background/aimsInvestigate if impaired vision is associated with reduced levels and differences in types of physical activity (PA) to identify barriers or enablers to achieving healthy PA levels.MethodsData from the Millennium Cohort Study of children born in the UK in 2000–2001 and followed-up to age 14 years (n=11 571). Using parental report on eye conditions coded by clinicians, children were categorised as having no, unilateral or bilateral impaired vision. Outcomes included objective accelerometer-derived time spent in moderate-to-vigorous physical activity (MVPA), and 16 PA types reported by parents, teachers and/or participants, covering physical education (PE), organised sports, self-organised sports and hobbies.ResultsOverall, 50% of 7-year-olds and subsequently 41% as 14-year-olds achieved the internationally recommended level of ≥60 MVPA min/day, irrespective of vision status, and mainly attributable to PE and organised sports. Bilateral impaired vision (vs none) was associated with parent-reported difficulties with PE (adjusted OR, 4.67; 95% CI, 2.31 to 9.41), self-rated poor ability in PE (3.21; 1.44 to 7.15) andnotenjoy indoor PA (0.48; 0.26 to 0.88). Unilateral impaired vision was associated with both parent-rated difficulties (1.80; 1.26 to 2.59) and teachers’ perception of low ability in PE (2.27; 1.57 to 3.28), and reduced odds of high participation in organised sports (0.77; 0.59 to 0.99). Age-related trajectories showed suboptimal PA in childhood tracked into adolescence, with no difference by vision status.ConclusionPopulation-wide programmes to increase PA levels in children should pay special attention to those with impaired vision and include early interventions to encourage participation and confidence in PE and organised sports, starting in primary school and maintained afterwards.

Refractive errors, particularly myopia, are the most common eye conditions, often leading to serious visual impairment. The age of onset is correlated with the severity of refractive error in adulthood observed in epidemiological and genetic studies and can be used as a proxy in refractive error genetic studies. To further elucidate genetic factors that influence refractive error, we analysed self-reported age of refractive error correction data from the UK Biobank European and perform genome-wide time-to-event analyses on the age of first spectacle wear (AFSW). Genome-wide proportional hazards ratio analyses were conducted in 340 318 European subjects. We subsequently assessed the similarities and differences in the genetic architectures of refractive error correction from different causes. All-cause AFSW was genetically strongly correlated (rg = −0.68) with spherical equivalent (the measured strength of spectacle lens required to correct the refractive error) and was used as a proxy for refractive error. Time-to-event analyses found genome-wide significant associations at 44 independent genomic loci, many of which (GJD2, LAMA2, etc.) were previously associated with refractive error. We also identified six novel regions associated with AFSW, the most significant of which was on chromosome 17q (P = 3.06 × 10−09 for rs55882072), replicating in an independent dataset. We found that genes associated with AFSW were significantly enriched for expression in central nervous system tissues and were involved in neurogenesis. This work demonstrates the merits of time-to-event study design in the genetic investigation of refractive error and contributes additional knowledge on its genetic risk factors in the general population.

Strabismus refers to an abnormal alignment of the eyes leading to the loss of central binocular vision. Concomitant strabismus occurs when the angle of deviation is constant in all positions of gaze and often manifests in early childhood when it is considered to be a neurodevelopmental disorder of the visual system. As such, it is inherited as a complex genetic trait, affecting 2–4% of the population. A genome-wide association study (GWAS) for self-reported strabismus (1345 cases and 65,349 controls from UK Biobank) revealed a single genome-wide significant locus on chromosome 17q25. Approximately 20 variants across the NPLOC4–TSPAN10–PDE6G gene cluster and in almost perfect linkage disequilibrium (LD) were most strongly associated (lead variant: rs75078292, OR = 1.26, p = 2.24E−08). A recessive model provided a better fit to the data than an additive model. Association with strabismus was independent of refractive error, and the degree of association with strabismus was minimally attenuated after adjustment for amblyopia. The association with strabismus was replicated in an independent cohort of clinician-diagnosed children aged 7 years old (116 cases and 5084 controls; OR = 1.85, p = 0.009). The associated variants included 2 strong candidate causal variants predicted to have functional effects: rs6420484, which substitutes tyrosine for a conserved cysteine (C177Y) in the TSPAN10 gene, and a 4-bp deletion variant, rs397693108, predicted to cause a frameshift in TSPAN10. The population-attributable risk for the locus was approximately 8.4%, indicating an important role in conferring susceptibility to strabismus. Electronic supplementary material The online version of this article (10.1007/s00439-019-02022-8) contains supplementary material, which is available to authorized users.

Background/aimsThere is a paucity of high-level evidence to support the management of childhood uveitis, particularly for those children without juvenile idiopathic arthritis uveitis (JIA). We undertook a modified Delphi consensus exercise to identify agreement in the management of chronic anterior uveitis (CAU), the most common manifestation of childhood disease.MethodsA four-round, two-panel process was undertaken between June and December 2017. Paediatric uveitis specialists identified through multiple sources, including a multicentre network (the Paediatric Ocular Inflammation Group), were invited to participate. They were asked whether they agreed with items derived from existing guidelines on the management of JIA-U when extrapolated to the population of all children with CAU. Consensus was defined as agreement greater than or equal to 75% of respondents.Results26 of the 38 (68%) invited specialists participated with the exercise, and response rates were 100% for rounds one to three, and 92% for round four. Consensus was reached on 23 of the 44 items. Items for which consensus was not reached included management at presentation, use of systemic and periocular steroids for children with severe disease and the role of conventional steroid sparing immunosuppressants beyond methotrexate.ConclusionThe areas of management uncertainty at the level of the group, as indicated by absence of consensus, reflect the areas where the evidence base is particularly poor. Our findings identify the key areas for the future research needed to ensure better outcomes for this blinding childhood ocular inflammatory disorders.

PURPOSE. Refractive errors, particularly myopia, are common and a leading cause of blind-ness. This study aimed to explore associations between medications and refractive error in an aging adult cohort and to determine whether childhood-onset refractive errors predict future medication use to provide novel insights into disease mechanisms.METHODS. The study compared the spherical equivalent values measured in 102,318 UK Biobank participants taking the 960 most commonly used medications. The strengths of associations were evaluated against the self-reported age of spectacle wear. The causality of refractive error changes was inferred using sensitivity and Mendelian randomization analyses.RESULTS. Anti-glaucoma drugs were associated with 1 to 2 diopters greater myopic refrac-tion, particularly in subjects who started wearing correction in the first two decades of life, potentially due to the association of higher intraocular pressure since early years with both myopia and, later in life, glaucoma. All classes of pain-control medications, including paracetamol, opiates, non-steroidal antiinflammatory drugs, and gabapentinoids, were associated with greater hyperopia (+0.68-1.15 diopters), after correction for deprivation, education, and polypharmacy and sensitivity analyses for common diagnoses. Oral hypoglycemics (metformin, gliburonide) were associated with myopia, as was allopurinol, and participants using bronchodilators (ipratropium and salbutamol) were more hyperopic.CONCLUSIONS. This study finds for the first time, to our knowledge, that medication use is associated with refractive error in adults. The novel finding that analgesics are associated with hyperopic refraction, and the possibility that multisite chronic pain predisposes to hyperopia, deserves further research. Some drugs, such as antihyperglycemic or bronchodilators, may directly alter refractive error. Intraocular pressure appears causative for myopia.

Objectives This study aimed to investigate associations between persisting amblyopia into adulthood and its “real-life” impacts and inform the current debate about the value of childhood vision screening programs. Methods Associations between persisting amblyopia and diverse socioeconomic, health, and well-being outcomes were investigated in multivariable-adjusted (sex, age, ethnicity, deprivation) regression models, with 126 400 participants (aged 40-70 years) of the UK Biobank with complete ophthalmic data. Analysis by age group (cohort 1, 60-70 years; cohort 2, 50-59 years; cohort 3, 40-49 years) assessed temporal trends. Results Of 3395 (3%) participants with confirmed amblyopia, overall 77% (2627) had persisting amblyopia, declining from 78% in cohort 1 to 73% in cohort 3. The odds of persisting amblyopia were 5.91 (5.24-6.66) and 2.49 (2.21-2.81) times greater in cohort 1 and cohort 2, respectively, than cohort 3. The odds were also higher for more socioeconomically deprived groups and for any “other than white” ethnicity. Reduced participation in sport, adverse general and mental health, and well-being were all independently associated with persisting amblyopia, with the strongest associations in the youngest cohorts. Associations with lower educational attainment and economic outcomes were only evident in the oldest cohort. Conclusions There has been a decline in the overall frequency of persisting amblyopia since the introduction of universal child vision screening in the United Kingdom. Nevertheless, most adults treated for amblyopia in childhood have persisting vision deficits. There was no evidence that persisting amblyopia has vision-mediated effects on educational, employment-related, or economic outcomes. The observed adverse outcomes were largely those not directly mediated by vision. Patients undergoing treatment should be counseled about long-term outcomes.

Background Childhood visual impairment (VI) has a profound impact on many aspects of childhood and adolescence. This is well-documented in cross-sectional and/or quantitative studies utilizing self-report instruments which compare children with and without VI. Young people’s views on the experience of growing up with VI as a developmental, change-driven process remain largely unexplored. Methods As part of our broader research programme on quality of life of visually impaired children and young people in the United Kingdom, in-depth, semi-structured interviews were conducted between March and June 2015, with a stratified sample of 17 young people with VI, aged 16–19 years. An age-sensitive, empirically-based topic guide encouraged retrospective reflections on participants’ experiences of growing up with VI, including age-normative and vision-specific challenges. Results Descriptions of growing up with VI largely centered on an overarching higher-order theme labelled becoming me. Four themes representing everyday activities, attitudes, preferences and perceptions in relation to i) social relationships, ii) independence and responsibilities, iii) the future, and iv) rising to challenges emerged and were used by participants in their description of three stages in which they developed a sense of self: i) laying the foundations, ii) testing the waters, and iii) this is me. Differences in manifestation of VI influenced how young people made sense of their experiences and their sense of self. Conclusions Findings are discussed in relation to normative and vision-specific changes in psychosocial development during adolescence, including the development of identity. They highlight the need for ongoing monitoring of subjective well-being in a clinical population with a unique early life course trajectory.

Background: In the United Kingdom, children should undergo eye examinations by maternity/neonatal teams or family practitioners within the first 72 post-natal hours, and again by eight weeks of age, to detect cataract. We report the frequency, associated factors and outcome of ‘late’ detection of congenital cataract in the UK. Methods: A population based prospective cohort study examining outcomes for children undergoing cataract surgery in the first two years of life, in 2009 and 2010. Detection of cataract after the age of eight weeks was defined as ‘late’. We used multivariable regression models to investigate factors associated with late detection. Findings: Of 186 babies, 64 (34%) with truly congenital cataract were diagnosed after 8 weeks of age. This late detection was independently associated with premature birth, specifically moderate and late preterm birth (adjusted odds ratio 3.0, 95%CI 1·1-8·5). The presence of co-existent globe anomaly was protective against late detection (adjOR 0·4, 95% CI 0·2-0·9). Outcomes at five years after surgery were 3- to 4-fold worse in those detected late. Interpretation: Delayed intervention in congenital cataract leads to life-long visual disability and consequent cumulative individual and societal burden. Our findings suggest that, despite a universal screening programme, one in three infants requiring surgery are not detected within the optimal period. Furthermore, there appears to be a gap in ascertainment of children born moderate to late preterm. It is necessary to improve the effectiveness of the screening programme, in particular in relation to pre-term children. Funding: Ulverscroft, Academy of Medical Sciences, NIHR. Declaration of Interest: None to declare. Ethical Approval: The study was approved by the ethics committees through the UK National Health Service Health Research Authority (Research ethics reference 08/H0714/65).

Background Perimetry is important in the management of children with glaucoma, but there is limited evidence-based guidance on its use. We report an expert consensus-based study to update guidance and identify areas requiring further research. Methods Experts were invited to participate in a modified Delphi consensus process. Panel selection was based on clinical experience of managing children with glaucoma and UK-based training to minimise diversity of view due to healthcare setting. Questionnaires were delivered electronically, and analysed to establish ‘agreement’. Divergence of opinions was investigated and resolved where possible through further iterations. Results 7/9 experts invited agreed to participate. Consensus (≥5/7 (71%) in agreement) was achieved for 21/26 (80.8%) items in 2 rounds, generating recommendations to start perimetry from approximately 7 years of age (IQR: 6.75–7.25), and use qualitative methods in conjunction with automated reliability indices to assess test quality. There was a lack of agreement about defining progressive visual field (VF) loss and methods for implementing perimetry longitudinally. Panel members highlighted the importance of informing decisions based upon individual circumstances—from gauging maturity/capability when selecting tests and interpreting outcomes, to accounting for specific clinical features (e.g. poor IOP control and/or suspected progressive VF loss) when making decisions about frequency of testing. Conclusions There is commonality of expert views in relation to implementing perimetry and interpreting test quality in the management of children with glaucoma. However, there remains a lack of agreement about defining progressive VF loss, and utilising perimetry over an individuals’ lifetime, highlighting the need for further research.

Childhood uveitis is a chronic, sight threatening inflammatory eye condition. There are a complex range of different disorders within the collective term of uveitis. Children can have associated systemic inflammatory disorders, and are treated with systemic chemotherapies which need frequent monitoring. For many, the uveitis continues to be active in adulthood. Care for children with uveitis is multi-centre and multi-disciplinary. A child’s primary care team may be located in a geographically distant location, acting as an obstacle to informing teams at local hospitals, particularly when children present acutely with problems associated with their eye disease, systemic disease or treatment. It can also be a challenge to educate young people about their disease, which is vital to support transition. A paper based ‘Uveitis Passport’ existed to support self-care for adults with uveitis. This paper based personal record was well received, but was not designed for use in children and young people. We have undertaken a project to create a digital mobile app specifically aimed at children to support them, and their families, to take control of their condition. In collaboration with UCL computer science, through the industry exchange network, researchers at GOSH and UCL GOS Institute of Child Health developed a mobile app to support Uveitis self-management. The adult ‘passport’ content was modified with the support of children and families. The application front-end was developed in Ionic. The back-end consists of an internal SQLite Database that provides the mobile app with direct read and write access to the data, stored locally in a single file. The mobile app developed allows patients to record important information about their condition. The app will support patient self-management, and empower patients when accessing services outside of their normal care team. This app could be modified to support a variety of childhood chronic conditions.

Background Severe microcephaly is defined by WHO as a head circumference (HC) more than 3 standard deviations below mean ( Aim To report the incidence, characteristics and causes of severe microcephaly diagnosed in children aged under one year in the UK and Ireland. Methods Active surveillance through the British Paediatric Surveillance Unit for 13 months from October 2017 to ascertain all live born children aged under 1 year who were diagnosed during this period with microcephaly or noted to have a HC The annual incidence of severe microcephaly was calculated for infants with HC Results The annual incidence of severe microcephaly (HC Conclusions The number of children with confirmed severe microcephaly was fewer than estimates based on European congenital anomaly registers. Infants of Asian ethnicity and those born preterm were over-represented. Most children were still under investigation for the cause of the microcephaly. Over three-quarters of children already demonstrated neurological abnormalities; further follow-up will capture later neurodevelopmental outcomes.

Background/aimsAnterior segment optical coherence tomography (AS-OCT) assessment of anterior chamber inflammation is an emerging tool. We describe the performance of AS-OCT in a paediatric population.MethodsA mixed-methods prospective study, using routine clinical assessment as reference standard, and AS-OCT, with Tomey CASIA2 or Heidelberg Spectralis HS1, as index test, with data collected on patient perceptions of imaging. Repeatability, diagnostic indices, responsiveness to clinical change and clinical correlations of imaging-based metrics (image cell count, size, density and brightness) were assessed, with construction of receiver operated characteristic curves. Exploratory thematic analysis of responses from families was undertaken.ResultsA total of 90 children (180 eyes) underwent imaging. Bland Altman limits of agreement for CASIA2 repeatability ranged from +17 cells (95% CI 13.6 to 21.1) to −19 cells (95% CI −15.6 to −23.2) and HS1 from +1 (95% CI 0.9 to 1.2) to −1.0 (−1.2 to −0.8) cells. CASIA2 imaging had higher sensitivity of 0.92 (95% CI 0.78 to 0.97) vs HS1 imaging 0.17 (95% CI 0.07 to 0.34), with positive correlation between clinical grade and CASIA2 cell count (coefficient 12.8, p=0.02, 95% CI 2.2 to 23.4). Change in clinical grade at follow-up examinations correlated with change in image based ‘cell’ count (r2=0.79, pConclusionOur findings suggest that OCT-based imaging holds the promise of deeper understanding of disease, improved patient experience and more granular monitoring of activity with resultant improved outcomes, but further work is needed to refine acquisition and analysis protocols.

BackgroundAmblyopia is a neurodevelopmental condition causing reduced vision, for which programmes of whole population child vision screening exist throughout the world. There is an ongoing debate about the value of screening due to the lack of evidence about meaningful functional impacts of amblyopia. Our objective was to determine whether amblyopia is associated with school readiness and early cognitive performance.Methods and findingsData from the prospective Millennium Cohort Study of children born in the United Kingdom in 2000-01 and followed-up to age 7 years (n = 13,967). Using parental self-report on eye conditions and treatment coded by clinical reviewers, participants were grouped into no eye conditions, strabismus alone, refractive amblyopia, or strabismic/mixed (refractive plus strabismic) amblyopia. The outcomes were poor school readiness using Bracken School Readiness Assessment 10 points) irrespective of whether treatment had already started. The age-related cognitive trajectories of children with amblyopia did not differ from those without any eye conditions for either NV (p = 0.62) or PC (p = 0.51). These associations are at population rather than individual level, so it might be that some individuals with amblyopia did experience significant adverse outcomes that are not captured by summary statistics.ConclusionsAmblyopia is not significantly associated with adverse cognitive performance and trajectories in early schooling and there is no evidence that this is due to a mediating effect of treatment. Although amblyopia combined with strabismus is associated with poor school readiness, this is not translated into poor cognitive performance. These novel findings may explain the lack of association reported between amblyopia and educational outcomes in adult life and suggest that the impact of amblyopia on education is not of itself a justification for whole population child vision screening aimed at detecting this disorder.

Refractive errors, in particular myopia, are a leading cause of morbidity and disability world-wide. Genetic investigation can improve understanding of the molecular mechanisms underlying abnormal eye development and impaired vision. We conducted a meta-analysis of genome-wide association studies involving 542,934 European participants and identified 336 novel genetic loci associated with refractive error. Collectively, all associated genetic variants explain 18.4% of heritability and improve the accuracy of myopia prediction (AUC=0.75). Our results suggest that refractive error is genetically heterogeneous, driven by genes participating in the development of every anatomical component of the eye. In addition, our analyses suggest that genetic factors controlling circadian rhythm and pigmentation are also involved in the development of myopia and refractive error. These results may make possible predicting refractive error and the development of personalized myopia prevention strategies in the future., Reporting summary Further information on research design is available in the Nature Research Reporting Summary linked to this article.

Background We investigated the incidence and causes of sight-threatening diabetes-related eye disease in children living with diabetes in the UK, to inform the national eye screening programme and enable monitoring of trends. Methods We undertook a prospective active national surveillance via the British Ophthalmic Surveillance Unit. Eligible cases were children aged 18 years or younger, with type 1 or 2 diabetes, newly diagnosed between January 2015 and February 2017 with sight-threatening diabetic eye disease. Results Eight children were reported. The annual incidence of all sight-threatening diabetes-related eye disease requiring referral to an ophthalmologist among children living with diabetes (n=8) in the UK was 1.21 per 10 000 person-years (95% CI 0.52 to 2.39) and was largely attributable to cataract (n=5) 0.76 per 10 000 person-years (95% CI 0.25 to 1.77). The incidence of sight-threatening diabetic retinopathy (n=3) among those eligible for screening (12 to 18 year-olds living with diabetes) was 1.18 per 10 000 person-years (95% CI 0.24 to 3.46). No subjects eligible for certification as visually impaired or blind were reported. Conclusions Secondary prevention of visual disability due to retinopathy is currently the sole purpose of national eye screening programmes globally. However, the rarity of treatment-requiring retinopathy in children/young people living with diabetes, alongside growing concerns about suboptimal screening uptake, merit new consideration of the utility of screening for primary prevention of diabetes-related morbidity by using the screening event and findings as a catalyst for better diabetes self-management.

AimsWe compared feasibility, quality and outcomes of visual field (VF) testing in children with neuro-ophthalmic disease between the discontinued ‘gold-standard’ Goldmann and Octopus perimeters.MethodsChildren with neuro-ophthalmic disease, attending Great Ormond Street Hospital, London, were assessed using standardised protocols by one examiner in a single sitting, using Goldmann and Octopus kinetic perimetry. Outputs were classified to compare severity of loss and defect type. Test quality was assessed using both qualitative and quantitative methods.ResultsThirty children (40% female) aged 5–15 years participated. Goldmann perimetry was completed in full by 90.0% vs 72.4% for Octopus. Inability to plot the blind spot was the most common reason for not completing testing. Over 75% completed a test in ≤20 min. Duration was similar between perimeters (paired t-test, mean difference: 0.48min (−1.2, 2.2), p=0.559). The lowest quality tests were for Octopus perimetry in children 2=1.0, p=0.317). There was broad agreement between Goldmann and Octopus outputs (good quality, n=21, Bland-Altman, mean difference for isopters I4e (−514.3 deg2(−817.4, –211.2), p=0.814), I2e (−575.5 deg2(−900.1, –250.9), p=0.450) and blind spot (20.8 deg2(5.7, 35.8), p=0.451)). However, VF severity grades and defect type matched in only 57% and 69% of tests, respectively. Octopus perimetry underestimated severe VF defects.ConclusionsInformative perimetry is feasible in children ≥8 years with neuro-ophthalmic conditions, with either Goldmann or Octopus perimeters. However, meaningful differences exist between the two approaches with implications for consistency in longitudinal assessments.

Background To assess cross-cultural validity between Dutch and English versions of the FVQ_CYP, a patient-reported outcome measure developed in the United Kingdom (UK) for children and adolescents with (severe) visual impairment or blindness (VI for brevity) to measure functional vision. Methods The 36-item FVQ_CYP was translated and adapted into Dutch using standard guidelines. The questionnaire was administered to Dutch children and adolescents aged 7–17 years (N = 253) with impaired vision (no restrictions regarding acuity). Data were compared to existing UK data of children and adolescents aged 10–15 years (N = 91) with VI (acuity LogMar worse than 0.48). As with the original UK FVQ_CYP validation, a rating scale model (RSM) was applied to the Dutch data. Results Minor adaptations were needed in translation-rounds. Significant differences in item responses were found between the Dutch and UK data. Item response theory assumptions were met, but fit to the RSM was unsatisfactory. Therefore, psychometric properties of the Dutch FVQ_CYP were analysed irrespective of the original model and criteria used. A graded response model led to the removal of 12 items due to missing data, low information, overlapping content and limited relevance to Dutch children. Fit indices for the remaining 24 items were adequate. Conclusions Differences in population characteristics, distribution of responses, non-invariance at the model level and small sample sizes challenged the cross-cultural validation process. However, the Dutch adapted FVQ_CYP showed high measurement precision and broad coverage of items measuring children’s functional vision. The underlying reasons for differences between countries in instrument performance are discussed with implications for future studies.

BackgroundRefractive error is an increasing global public health concern that requires robust and reliable research to identify modifiable risk factors and provide accurate estimates of population burden. We investigated the impact of reclassification of individuals when using different threshold values of spherical equivalent (SE) to define myopia, on estimates of frequency, distribution and associations with risk factors, to inform current international initiatives to standardise definitions.MethodsA random sample of 1985 individuals from the 1958 British birth cohort, at age 44, had autorefraction and self-reported on educational attainment and social class.Refraction status assigned in three different models using SE: (A) moderate to high myopia −3 diopters (D) or more extreme (≤−3.00D), (B) hypermetropia +1.00D or more extreme (≥+1.00D) and (C) mild myopia using three different thresholds: −1.00D, −0.75D or −0.50D, hence reciprocal changes in definition of emmetropia.ResultsFrequency estimates and associations with risk factors altered significantly as the threshold value for myopia moved towards SE 0.0D: prevalence of mild myopia increased from 28% to 47%, the association with highest educational attainment attenuated and with higher social class strengthened, with changes in risk ratios of approximately 20%.ConclusionEven small changes in the threshold definition of myopia (±0.25D) can significantly affect the conclusions of epidemiological studies, creating both false-positive and false-negative associations for specific risk factors. An international classification for refractive error, empirically evidenced and cognisant of the question(s) being addressed and the population(s) being studied, is needed to serve better translational research, practice and policy.

An estimated 1.4 million of the world's children are blind. A blind child is more likely to live in socioeconomic deprivation, to be more frequently hospitalised during childhood and to die in childhood than a child not living with blindness. This update of a previous review on childhood visual impairment focuses on emerging therapies for children with severe visual disability (severe visual impairment and blindness or SVI/BL).For children in higher income countries, cerebral visual impairment and optic nerve anomalies remain the most common causes of SVI/BL, while retinopathy of prematurity (ROP) and cataract are now the most common avoidable causes. The constellation of causes of childhood blindness in lower income settings is shifting from infective and nutritional corneal opacities and congenital anomalies to more resemble the patterns seen in higher income settings. Improvements in maternal and neonatal health and investment in and maintenance of national ophthalmic care infrastructure are the key to reducing the burden of avoidable blindness. New therapeutic targets are emerging for childhood visual disorders, although the safety and efficacy of novel therapies for diseases such as ROP or retinal dystrophies are not yet clear. Population-based epidemiological research, particularly on cerebral visual impairment and optic nerve hypoplasia, is needed in order to improve understanding of risk factors and to inform and support the development of novel therapies for disorders currently considered 'untreatable'.