The prevalence of uncorrected refractive errors in underserved rural areas

The Reliability and Acceptability of RDx-Based Tele-Controlled Subjective Refraction Compared with Traditional Subjective Refraction

Purpose

The purpose of this study was to compare the reliability and acceptability of tele-controlled subjective refraction supported by RDx, a new technique that involves optical software designed for controlling phoropters remotely, to traditional subjective refraction.

Methods

Sixty-five participants underwent tele-controlled subjective refraction and traditional subjective refraction randomly and nine of them underwent the second tele-controlled subjective refraction measurement on the same day. After their examinations, we distributed a validated satisfaction questionnaire to each participant. The elapsed time taken for refraction, sphere (S), cylinder (C), spherical equivalent (SE), vertical and oblique cylindrical vectors (J₀ and J₄₅), and best corrected visual acuity (BCVA) were compared. Age and refractive error type were included as covariates. Bland-Altman analysis was used to assess the agreement between both methods of refraction.

Results

The mean age was 20.5 ± 5.9 years for all participants (aged 9 to 40 years); 57% were female participants. The repeatability analysis of tele-controlled method showed no significant differences for all parameters (P > 0.05). We found no statistical differences (P > 0.05) between tele-controlled subjective refraction and traditional subjective refraction for all parameters in either group. The mean difference and 95% limits of agreement for SE, J₀, and J₄₅ were −0.03 ± 0.36 diopters (D), −0.00 ± 0.57 D, and −0.01 ± 0.79 D, respectively. The tele-controlled method took more time to perform than the traditional one (P < 0.05). Completed questionnaires were returned by 55 participants (85%), and they showed high satisfaction and acceptance of the tele-controlled method (98%).

Conclusions

Tele-controlled subjective refraction results agreed with traditional subjective refraction for all refraction components except for cylinder vectors. In addition, the broad acceptability of tele-controlled subjective refraction means practicability in clinical practice.

Translation Relevance

The RDx-based tele-controlled method can provide an alternative to subjective refraction, especially in areas that lack experienced optometrists.

Risk Factors for Uncorrected Refractive Error: Persian Cohort Eye Study - Rafsanjan Center

Purpose

To determine the prevalence of visually significant uncorrected refractive error (URE) in Rafsanjan and investigate the related factors. URE is the leading cause of visual impairment (VI) which causes the second-highest number of years lived with disability. The URE is a preventable health problem.

Methods

In this cross-sectional study participants from Rafsanjan who were 35-70 years were enrolled between 2014 and 2020. Demographic and clinical characteristics data were gathered, and eye examination was performed. Visually significant URE was defined as present if habitual visual acuity was (HVA; visual acuity with present optical correction) >0.3 logMAR in the best eye and the visual acuity of that eye showed >0.2 logMAR improvement after the best correction. Logistic regression was used to determine the association between predicting variables (age, sex, wealth, education, employment, diabetes, cataract, and refractive error characteristics) and outcome (URE).

Results

Among the 6991 participants of Rafsanjan subcohort of the Persian Eye Cohort, 311 (4.4%) had a visually significant URE. Diabetes was significantly more prevalent in the participants with visually significant URE, at 18.7% versus 13.1% in patients without significant URE (P = 0.004). In the final model, each year of increase in age was associated with 3% higher URE (95% confidence interval [CI]: 1.01-1.05). In comparison to low hyperopia, participants with low myopia had 5.17 times more odds of visually significant URE (95% CI: 3.38-7.93). However, antimetropia decreased the risk of visually significant URE (95% CI: 0.02-0.37).

Conclusion

Policymakers should pay special attention to elderly patients with myopia to effectively reduce the prevalence of visually significant URE.

Visual impairments amongst preschool and school attendees: A scoping review of vision school screening in Nigeria and Kenya

Background: The United Nations Convention on the Rights of the Child emphasises the importance of quality education and good health. Vision problems affect the academic performance of schoolchildren in developing and under-resourced countries. The most prevalent vision problem amongst children is uncorrected refractive errors (URE).Aim: To gain knowledge about vision problems and visual impairments (VI) through school vision screening amongst children in Kenya and Nigeria.Method: A scoping review of online databases (Web of Science and PubMed) and one African registry (African Journals Online) for articles from January 2011 until April 2021 was conducted. The authors included 26 articles of the 439 screened.Results: The literature revealed inconsistencies in how VI was defined. The main cause of vision problems is URE. Furthermore, there is a lack of systematic school vision screening tools and programmes.Conclusion: Efficient eye care services to schoolchildren aged 3–18 years in Kenya and Nigeria must involve multiple disciplinary interventions and governmental responsibility. Collaboration models between public and private health sectors, nongovernmental organisations and families are necessary to prevent VI amongst children. Better vision enhances school performance.

Estimating need and coverage for five priority assistive products: a systematic review of global population-based research

INTRODUCTION

To improve access to assistive products (APs) globally, data must be available to inform evidence-based decision-making, policy development and evaluation, and market-shaping interventions.

METHODS

This systematic review was undertaken to identify studies presenting population-based estimates of need and coverage for five APs (hearing aids, limb prostheses, wheelchairs, glasses and personal digital assistants) grouped by four functional domains (hearing, mobility, vision and cognition).

RESULTS

Data including 656 AP access indicators were extracted from 207 studies, most of which (n=199, 96%) were cross-sectional, either collecting primary (n=167) or using secondary (n=32) data. There was considerable heterogeneity in assessment approaches used and how AP indicators were reported; over half (n=110) used a combination of clinical and self-reported assessment data. Of 35 studies reporting AP use out of all people with functional difficulty in the corresponding functional domains, the proportions ranged from 4.5% to 47.0% for hearing aids, from 0.9% to 17.6% for mobility devices, and from 0.1% to 86.6% for near and distance glasses. Studies reporting AP need indicators demonstrated >60% unmet need for each of the five APs in most settings.

CONCLUSION

Variation in definitions of indicators of AP access have likely led to overestimates/underestimates of need and coverage, particularly, where the relationship between functioning difficulty and the need for an AP is complex. This review demonstrates high unmet need for APs globally, due in part to disparate data across this sector, and emphasises the need to standardise AP data collection and reporting strategies to provide a comparable evidence base to improve access to APs.

Economic Inequality in Visual Impairment: A Study in Deprived Rural Population of Iran

Purpose:

To determine economic inequality in visual impairment (VI) and its determinants in the rural population of Iran.

Methods:

In this population-based, cross-sectional study, 3850 individuals, aged 3–93 years were selected from the north and southwest regions of Iran using multi-staged stratified cluster random sampling. The outcome was VI, measured in 20 feet. Economic status was constructed using principal component analysis on home assets. The concentration index (C) was used to determine inequality, and the gap between low and high economic groups was decomposed to explained and unexplained portions using the Oaxaca–Blinder decomposition method.

Results:

Of the 3850 individuals that were invited, 3314 participated in the study. The data of 3095 participants were finally analyzed. The C was −0.248 (95% confidence interval [CI]: −0.347 - −0.148), indicating a pro-poor inequality (concentration of VI in low economic group). The prevalence (95% CI) of VI was 1.72% (0.92–2.52) in the high economic group and 10.66% (8.84–12.48) in the low economic group with a gap of 8.94% (6.95–10.93) between the two groups. The explained and unexplained portions comprised 67.22% and 32.77% of the gap, respectively. Among the study variables, age (13.98%) and economic status (80.70%) were significant determinants of inequality in the explained portion. The variables of education (coefficient: −4.41; P < 0.001), age (coefficient: 14.09; P < 0.001), living place (coefficient: 6.96; P: 0.006), and economic status (coefficient: −7.37; P < 0.001) had significant effects on inequality in the unexplained portion.

Conclusions:

The result showed that VI had a higher concentration in the low economic group, and the major contributor of this inequality was economic status. Therefore, policymakers should formulate appropriate interventions to improve the economic status and alleviate economic inequality.

Prevalence of Uncorrected Refractive Error and Its Risk Factors; Tehran Geriatric Eye Study (TGES)

Purpose: To determine the age-sex-standardized prevalence of uncorrected refractive error and its determinantsMethods: This population-based cross-sectional study was conducted on 3310 people aged≥ 60 years in Tehran, Iran in 2019. Need for spectacles was defined as uncorrected visual acuity worse than 20/40 in better eye that could be corrected to more than 20/40 with suitable spectacles. Met need was defined as proportion of individuals with need for spectacles whose visual acuity was 20/40 or better with current spectacles. Unmet need was defined as proportion of individuals with need for spectacles who needed but did not have spectacles or their visual acuity was worse than 20/40 with current spectacles while suitable spectacles improved their visual acuity to 20/40 or better.Results: The age-sex-standardized prevalence of need for spectacles, met need, and unmet need was 16.67% (95% CI: 15.33-18.09), 7.81% (95% CI: 6.95-8.78), and 8.85% (95% CI: 7.77-10.07), respectively. Myopic subjects had the highest prevalence of need for spectacles (24.06%, 95% CI: 21.47-26.87). The odds ratio of met and unmet need in subjects≥ 80 years versus those aged 60-65 years was 0.36 (p-value: 0.009) and 2.34 (p-value: <0.001), respectively. The odds ratio of met and unmet need in subjects with a university education versus illiterate subjects was 1.72 (p-value: 0.045) and 0.42 (p-value: 0.007), respectively.Conclusion: The prevalence of uncorrected refractive error was lower in this study compared to previous studies. The met need rate was lower in subjects with older age and lower education levels.