The prevalence of myopia increases with both age and grade for children attending school. The current study aimed to distinguish the effects of aging and grade on myopia.
Grade 1 students (706 at ...baseline in 2009, mean age 6.56 ± 0.29 years, range 6.00 to 6.99 years old, 55.5% boys) were followed up until 2012. Cycloplegic spherical equivalent (SE) was measured annually.
The sample in a grade was divided into three 4-month age blocks according to their birth month. Within each grade, there were no significant differences in SE between age blocks (all P > 0.05), despite an age range of one year. More myopic SE was observed in the youngest block of grade 2 compared to the oldest block of grade 1 (difference, -0.36 ± 0.08 D; P < 0.001), although age of the two blocks only differed by four months. Similarly, more myopic SE were found in the youngest block in grade 3 than the oldest block in grade 2 (differences, -0.50 ± 0.10 D; P < 0.001) and in the youngest block in grade 4 than the oldest block in grade 3 (differences, -0.82 ± 0.14 D; P < 0.001).
Exposure to schooling, rather than age, appears to be the major driver of refractive development, at least in the early years of schooling. Interventions during this period, involving reductions in educational pressure and increased time outdoors may have major effects on the subsequent development of myopia.
Zn-doped SnO2 nanorods clusters with controllable size (the length and the diameter of nanorods) are prepared by adjusting the Zn2+ concentration in the precursor solution using a facile hydrothermal ...process. The as-synthesized samples are characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, and energy-dispersive X-ray spectroscopy (EDS). With an increase of the molar ratio of Zn2+/Sn4+ in the solution, the length of the Zn-doped SnO2 nanorods gradually increases, and the average length of the nanorods reaches the maximum of 239nm at 0.133. However, when the molar ratio of Zn2+/Sn4+ is increased to 0.2, the length of the nanorods decreases accompanied with the generation of Zn2SnO4 phase. The Zn-doped SnO2 nanorods grow along the 112 direction and the possible growth mechanism is proposed. The gas-sensing properties of the obtained Zn-doped SnO2 samples are tested towards methanol gas. And, it is found the composition-morphology-performance relationship that the more the doping content of Zn, the longer the length of nanorods and the higher the response to methanol, which is significant for the preparation and the design of gas-sensing materials with the high performance.
Electronic medical records provide large-scale real-world clinical data for use in developing clinical decision systems. However, sophisticated methodology and analytical skills are required to ...handle the large-scale datasets necessary for the optimisation of prediction accuracy. Myopia is a common cause of vision loss. Current approaches to control myopia progression are effective but have significant side effects. Therefore, identifying those at greatest risk who should undergo targeted therapy is of great clinical importance. The objective of this study was to apply big data and machine learning technology to develop an algorithm that can predict the onset of high myopia, at specific future time points, among Chinese school-aged children.
Real-world clinical refraction data were derived from electronic medical record systems in 8 ophthalmic centres from January 1, 2005, to December 30, 2015. The variables of age, spherical equivalent (SE), and annual progression rate were used to develop an algorithm to predict SE and onset of high myopia (SE ≤ -6.0 dioptres) up to 10 years in the future. Random forest machine learning was used for algorithm training and validation. Electronic medical records from the Zhongshan Ophthalmic Centre (a major tertiary ophthalmic centre in China) were used as the training set. Ten-fold cross-validation and out-of-bag (OOB) methods were applied for internal validation. The remaining 7 independent datasets were used for external validation. Two population-based datasets, which had no participant overlap with the ophthalmic-centre-based datasets, were used for multi-resource validation testing. The main outcomes and measures were the area under the curve (AUC) values for predicting the onset of high myopia over 10 years and the presence of high myopia at 18 years of age. In total, 687,063 multiple visit records (≥3 records) of 129,242 individuals in the ophthalmic-centre-based electronic medical record databases and 17,113 follow-up records of 3,215 participants in population-based cohorts were included in the analysis. Our algorithm accurately predicted the presence of high myopia in internal validation (the AUC ranged from 0.903 to 0.986 for 3 years, 0.875 to 0.901 for 5 years, and 0.852 to 0.888 for 8 years), external validation (the AUC ranged from 0.874 to 0.976 for 3 years, 0.847 to 0.921 for 5 years, and 0.802 to 0.886 for 8 years), and multi-resource testing (the AUC ranged from 0.752 to 0.869 for 4 years). With respect to the prediction of high myopia development by 18 years of age, as a surrogate of high myopia in adulthood, the algorithm provided clinically acceptable accuracy over 3 years (the AUC ranged from 0.940 to 0.985), 5 years (the AUC ranged from 0.856 to 0.901), and even 8 years (the AUC ranged from 0.801 to 0.837). Meanwhile, our algorithm achieved clinically acceptable prediction of the actual refraction values at future time points, which is supported by the regressive performance and calibration curves. Although the algorithm achieved balanced and robust performance, concerns about the compromised quality of real-world clinical data and over-fitting issues should be cautiously considered.
To our knowledge, this study, for the first time, used large-scale data collected from electronic health records to demonstrate the contribution of big data and machine learning approaches to improved prediction of myopia prognosis in Chinese school-aged children. This work provides evidence for transforming clinical practice, health policy-making, and precise individualised interventions regarding the practical control of school-aged myopia.
To examine the association between the longitudinal changes of axial length (AL) and height in Chinese children.
The study participants were recruited from the Guangzhou Twin Registry. AL and height ...were measured every year from 2006 to 2008. AL was measured using partial coherence laser interferometry. Height was measured with the participants standing without shoes. Bivariate correlation coefficients and a multivariate generalized regression model were used to calculate the association between the changes of AL and height. Data from the first-born twins were selected to present the results: The right eye was arbitrarily selected to represent AL of the specific individual.
Mean annual increases of AL and height were 0.22 (SD, 0.17) mm and 3.93 (SD, 3.02) cm, respectively. Correlations between AL and height were 0.47 (95% CI, 0.40-0.52) in 2006. The correlation between AL at 2006 and height at 2008 was 0.44 (95% CI, 0.37-0.51); the correlation between AL at 2008 and height at 2006 was 0.38 (95% CI, 0.32-0.45). These cross-trait cross-time correlation coefficients remained statistically significant after adjusting for age and sex. Plotting the changes of AL and height suggested that the changes of AL and height with age were concomitant; greater changes were observed in younger children.
The association between AL and height in cross-sectional analysis and longitudinal changes may suggest common pathways for the development of eye size and body size in children.
To assess the use of eye care and its predictors among diabetic patients in China.
Cross-sectional, clinic-based study.
Diabetic patients 18 years of age or older were recruited consecutively from an ...urban tertiary and community hospitals and from a rural clinic in Guangdong, China.
Information obtained by questionnaire and chart review included: demographic and socioeconomic status, knowledge about diabetic retinopathy (DR), and ocular and medical history.
Self-reported or chart history of an eye examination ever or within the preceding 12 months.
The participation rate among 889 eligible subjects was 92.7%. Among 824 participants (mean age, 62.6+/-12.9 years; 58.8% female), 550 (66.7%) had not been examined in the last year as recommended by the American Academy of Ophthalmology, and 356 (43.2%) had never been examined. For the rural hospital, these figures were 81.1% and 68.7%, respectively. In regression analyses, factors associated with having an eye examination in the last year were: attendance at urban hospitals (odds ratio OR, 3.46 P<0.001 and 1.76 P = 0.021 for the tertiary and community hospitals, respectively, compared with the rural clinic), higher DR knowledge score (OR, 1.24; P = 0.001), greater concern about vision loss (OR, 1.22; P = 0.007), and recommendation of regular eye examinations by the provider (OR, 2.36; P = 0.011). Predictors of ever having an eye examination were similar. Monthly income and health insurance status were not predictive of being examined.
These results suggest that the low proportion of diabetic receiving recommended annual eye examinations in China may be improved through patient and physician education.
Explicitly sharing individual level data in genomics studies has many merits comparing to sharing summary statistics, including more strict QCs, common statistical analyses, relative identification ...and improved statistical power in GWAS, but it is hampered by privacy or ethical constraints. In this study, we developed encG-reg, a regression approach that can detect relatives of various degrees based on encrypted genomic data, which is immune of ethical constraints. The encryption properties of encG-reg are based on the random matrix theory by masking the original genotypic matrix without sacrificing precision of individual-level genotype data. We established a connection between the dimension of a random matrix, which masked genotype matrices, and the required precision of a study for encrypted genotype data. encG-reg has false positive and false negative rates equivalent to sharing original individual level data, and is computationally efficient when searching relatives. We split the UK Biobank into their respective centers, and then encrypted the genotype data. We observed that the relatives estimated using encG-reg was equivalently accurate with the estimation by KING, which is a widely used software but requires original genotype data. In a more complex application, we launched a finely devised multi-center collaboration across 5 research institutes in China, covering 9 cohorts of 54,092 GWAS samples. encG-reg again identified true relatives existing across the cohorts with even different ethnic backgrounds and genotypic qualities. Our study clearly demonstrates that encrypted genomic data can be used for data sharing without loss of information or data sharing barrier.
To describe a new combined myopia and glaucoma visual field classification system in order to report the visual field defects in a population of mostly young Chinese high myopes aged 7-70 years.
A ...total of 1434 visual fields (including confirmatory repeats of abnormal defects) from 487 high myopes (sphere ≤-6.0 D) were analysed from the prospective Zhongshan Ophthalmic Center-Brien Holden Vision Institute (ZOC-BHVI) High Myopia Registry Study. The predefined classification definitions covering high myopia and glaucoma categories were: normal, enlarged blind spot, abnormal suspect and abnormal with nine subtypes. Two independent graders reviewed the first 150 of 1434 fields for initial grading calibration and the remaining 1284 fields were used to assess intergrader agreement. For the percentage distribution of visual fields, the repeats and unreliable fields were excluded, leaving 894 fields.
The intergrader agreement of this combined classification system was a κ value of 0.61 (95% CI 0.59 to 0.63). Among the 894 unique fields, the most common visual field was normal at 33.7% followed by enlarged blind spot at 25.6%. The per cent of 'arcuate-like' field defects (combining nasal step, early arcuate and advanced arcuate) was 16.1% with advanced arcuate at 3.4%.
A proposed combined visual field classification for high myopia and glaucoma demonstrates acceptable intergrader agreement. A total of 16.1% of defects in young high myopes were found to mimic classic glaucomatous defects. These subjects are being followed prospectively to assess which ones will progress to differentiate myopic from glaucomatous field defects.
Landslides represent a significant global natural hazard, threatening human settlements and the natural environment. The primary objective of the study was to develop a landslide susceptibility ...modeling approach that enhances prediction accuracy and informs land-use planning decisions. The study utilized a hybrid ensemble-based methodology to improve prediction accuracy and effectively capture the complexity of landslide susceptibility patterns. This approach harnessed the power of ensemble models, employing a bagging algorithm with base learners, including the reduced error pruning decision tree (REPTree) and functional tree (FT) models. Ensemble models are particularly valuable because they combine the strengths of multiple models, enhancing the overall performance and robustness of the landslide susceptibility prediction. The study focused on Yanchuan County, situated within the hilly and gully region of China’s Loess Plateau, known for its susceptibility to landslides, using sixteen critical landslide conditioning factors, encompassing topographic, environmental, and geospatial variables, namely elevation, slope, aspect, proximity to rivers and roads, rainfall, the normalized difference vegetation index, soil composition, land use, and more. Model performances were evaluated and verified using a range of metrics, including receiver operating characteristic (ROC) curves, trade-off statistical metrics, and chi-square analysis. The results demonstrated the superiority of the integrated models, particularly the bagging FT (BFT) model, in accurately predicting landslide susceptibility, as evidenced by its high area under the curve area (AUC) value (0.895), compared to the other models. The model excelled in both positive predictive rate (0.847) and negative predictive rate (0.886), indicating its efficacy in identifying landslide and non-landslide areas and also in the F-score metric with a value of 0.869. The study contributes to the field of landslide risk assessment, offering a significant investigation tool for managing and mitigating landslide hazards in Yanchuan County and similar regions worldwide.
To describe the prevalence of age-related macular degeneration (AMD) among older adults in rural southern mainland China.
Eligible persons aged 50 years or over were identified by geographically ...defined cluster sampling from Yangxi County, Guangdong Province, China. Participants underwent a standardised interview and comprehensive eye examinations from August to November in 2014. Digital retinal photographs were graded for AMD lesions using the Clinical Classification of Age-Related Macular Degeneration developed by the Beckman Initiative for Macular Research Classification Committee. Age-standardised prevalence of AMD and AMD lesions was calculated using the 2010 world population data and compared with those of other populations.
Of 5825 subjects who participated (90.7% response rate), 4881 (83.8%) had fundus photographs gradable for AMD. Early, intermediate and late AMD were present in 2003 (41.0%), 879 (18.0%) and 42 (0.86%) participants. The age-standardised prevalence of early, intermediate and late AMD was 40.4% (95% CI 39.6% to 41.2%), 17.6% (95% CI 17.0% to 18.2%) and 0.79% (95% CI 0.65% to 0.95%), respectively. Total AMD was more prevalent in men than in women (62.8% vs 57.1%).
AMD is an important public health concern for rural southern China, and the prevalence of AMD was higher in men than in women.
To document the distribution of uncorrected visual acuity (UCVA) in a defined population of Chinese preschoolers and to discuss its implications for vision referral.
Preschoolers aged 3 to 6 years ...old were recruited from kindergartens in Shenzen. Uncorrected visual acuity was estimated by using Early Treatment Diabetic Retinopathy Study Tumbling E charts, followed by cycloplegic refraction and ocular examination. The reference population was defined as children without clinically significant ocular abnormalities, with spherical equivalent refraction greater than -0.50 to less than +2.00 diopters (D), astigmatism less than 0.75 D, and anisometropia less than 2.00 D. The age-specific UCVA cutoffs were defined by the line where the single-sided 95th percentile of the reference population fell.
A total of 483 of the 1255 children enrolled were considered the reference population. The monocular UCVA cutoff fell on the line of 20/63 at age 3, 20/50 at age 4, and 20/40 at ages 5 and 6. Using no better than these lines as criteria generated referral rates of 9.4% to 27.8% in the general population at different ages, and detected 83.3% and more than 90.0% of those with myopia and amblyopia, respectively. Using uncorrected interocular difference of two or more lines referred 3.6% to 4.3% of the population but identified only approximately 20.0% of those with amblyopia.
Visual acuity is still developing in preschoolers even at age 6. Most children with myopia and amblyopia can be identified with age-specific, monocular UCVA cutoffs in vision screening using Tumbling E charts, with tolerable false-positive rates. Further studies are needed to define the age at which children without significant refractive errors reach 20/20 UCVA.