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The Cochrane Database of Systematic... Oct 2013The purpose of low-vision rehabilitation is to allow people to resume or to continue to perform daily living tasks, with reading being one of the most important. This is... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The purpose of low-vision rehabilitation is to allow people to resume or to continue to perform daily living tasks, with reading being one of the most important. This is achieved by providing appropriate optical devices and special training in the use of residual-vision and low-vision aids, which range from simple optical magnifiers to high-magnification video magnifiers.
OBJECTIVES
To assess the effects of reading aids for adults with low vision.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 1), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE, (January 1950 to January 2013), EMBASE (January 1980 to January 2013), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2013), OpenGrey (System for Information on Grey Literature in Europe) (www.opengrey.eu/), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov/) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 31 January 2013. We searched the reference lists of relevant articles and used the Science Citation Index to find articles that cited the included studies and contacted investigators and manufacturers of low-vision aids. We handsearched the British Journal of Visual Impairment from 1983 to 1999 and the Journal of Visual Impairment and Blindness from 1976 to 1991.
SELECTION CRITERIA
This review includes randomised and quasi-randomised trials in which any device or aid used for reading had been compared to another device or aid in people aged 16 or over with low vision as defined by the study investigators.
DATA COLLECTION AND ANALYSIS
At least two authors independently assessed trial quality and extracted data.
MAIN RESULTS
We included nine small studies with a cross-over-like design (181 people overall) and one study with three parallel arms (243 participants) in the review. All studies reported the primary outcome, results for reading speed.Two studies including 92 participants found moderate- or low-quality evidence suggesting that reading speed is higher with stand-mounted electronic devices or electronic devices with the camera mounted in a 'mouse' than with optical magnifiers, which in these trials were generally stand-mounted or, less frequently, hand-held magnifiers or microscopic lenses. In another study of 20 participants there was moderate-quality evidence that optical devices are better than head-mounted electronic devices (four types).There was low-quality evidence from three studies (93 participants) that reading using head-mounted electronic devices is slower than with stand-based electronic devices. The technology of electronic devices may have changed and improved since these studies were conducted.One study suggested no difference between a diffractive spectacle-mounted magnifier and either refractive (15 participants) or aplanatic (15 participants) magnifiers.One study of 10 people suggested that several overlay coloured filters were no better and possibly worse than a clear filter.A parallel-arm study including 243 participants with age-related macular degeneration found that custom or standard prism spectacles were no different from conventional reading spectacles, although the data did not allow precise estimates of performance to be made.
AUTHORS' CONCLUSIONS
There is insufficient evidence on the effect of different types of low-vision aids on reading performance. It would be necessary to investigate which patient characteristics predict performance with different devices, including costly electronic devices. Better-quality research should also focus on assessing sustained long-term use of each device. Authors of studies testing several devices on the same person should consider design and reporting issues related to their sequential presentation and to the cross-over-like study design.
Topics: Adult; Eyeglasses; Humans; Lenses; Macular Degeneration; Optical Devices; Randomized Controlled Trials as Topic; Reading; Sensory Aids; Vision, Low; Visual Acuity; Visually Impaired Persons
PubMed: 24154864
DOI: 10.1002/14651858.CD003303.pub3 -
Middle East African Journal of... 2017The purpose of this study is to provide a pooled estimate of moderate-to-severe visual impairment (MSVI) and blindness in Iran for people 50 years and over and to... (Review)
Review
PURPOSE
The purpose of this study is to provide a pooled estimate of moderate-to-severe visual impairment (MSVI) and blindness in Iran for people 50 years and over and to identify the major causes through systematic review.
MATERIALS AND METHODS
International (PubMed, ISI Web of Science, and Scopus) and national databases (Scientific Information Database, Barakat Knowledge Network System, Iran Databank of Ophthalmology Research, and Magiran) databases were searched. Following relevance assessment and critical appraisal, eight studies were included. A funnel plot was drawn to explore the stability for estimation. Single-variable meta-regression analysis was applied for heterogeneity assessment, and a random effect model was used (but no significant source for the observed heterogeneity was found).
RESULTS
Age-standardized pooled estimate of MSVI was 4.24% (95% confidence interval [CI]: 2.92-5.56); 3.98% (95% CI: 2.37-5.59) for men, and 4.08% (95% CI: 2.95-5.21) for women. Blindness (visual acuity <3/60) prevalence was 1.31% (95% CI: 1.23-1.39); 0.96% (95% CI: 0.89-1.03) for men, and 1.13% (95% CI: 1.06-1.20) for women. Causes of visual impairment (VI) were cataract (40.23%), amblyopia (12.03%), corneal opacity (9.63%), age-related macular degeneration (9.31%), diabetic retinopathy (4.94%), and glaucoma (3.67%).
CONCLUSION
VI prevalence in the 50 years and older population in Iran seems significantly better than the corresponding global estimates. A rough 60% rate of treatable VI was estimated, mostly attributable to unoperated cataract.
Topics: Blindness; Databases, Factual; Eye Diseases; Female; Humans; Iran; Male; Prevalence; Social Perception; Vision, Low; Visually Impaired Persons
PubMed: 29279656
DOI: 10.4103/meajo.MEAJO_168_16 -
The National Medical Journal of India 2018
Topics: Color Vision Defects; Education, Medical; Health Personnel; Humans; India; Prevalence; Students, Medical; Visually Impaired Persons; Workplace
PubMed: 30829218
DOI: 10.4103/0970-258X.253161 -
Eye (London, England) Mar 2022To determine the relationship between visual impairment and other disabilities in a developing country.
OBJECTIVE
To determine the relationship between visual impairment and other disabilities in a developing country.
METHODS
In this cross-sectional ancillary study, all individuals 50 years and older in 18 communities in the Chitwan region of Nepal were administered visual acuity screening and the Washington Group Short Set (WGSS) of questions on disability. The WGSS elicits a 4-level response for six disability domains: vision, hearing, walking/climbing, memory/concentration, washing/dressing, and communication. The association between visual impairment and disability was assessed with age- and sex-adjusted logistic regression models.
RESULTS
Overall, 4719 of 4726 individuals successfully completed visual acuity and disability screening. Median age of participants was 61 years (interquartile range: 55-69 years), and 2449 (51.9%) were female. Participants with vision worse than 6/60 in the better-seeing eye were significantly more likely to be classified as having a disability in vision (OR 18.4, 95% CI 9.9-33.5), walking (OR 5.3, 95% CI 2.9-9.1), washing (OR 9.4, 95% CI 4.0-21.1), and communication (OR 5.0, 95% CI 1.7-13.0), but not in hearing (OR 0.6, 95% CI 0.006-2.2) or memory (OR 2.2, 95% CI 0.7-5.1).
CONCLUSIONS
Visually impaired participants were more likely to self-report disabilities, though causality could not be ascertained. Public health programs designed to reduce visual impairment could use the WGSS to determine unintended benefits of their interventions.
Topics: Aged; Blindness; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Vision Disorders; Vision, Low; Visually Impaired Persons
PubMed: 33731892
DOI: 10.1038/s41433-021-01498-x -
Ophthalmic Epidemiology 2013To describe a systematic review of population-based prevalence studies of visual impairment (VI) and blindness worldwide over the past 32 years that informs the Global... (Review)
Review
PURPOSE
To describe a systematic review of population-based prevalence studies of visual impairment (VI) and blindness worldwide over the past 32 years that informs the Global Burden of Diseases, Injuries and Risk Factors Study.
METHODS
A systematic review (Stage 1) of medical literature from 1 January 1980 to 31 January 2012 identified indexed articles containing data on incidence, prevalence and causes of blindness and VI. Only cross-sectional population-based representative studies were selected from which to extract data for a database of age- and sex-specific data of prevalence of four distance and one near vision loss categories (presenting and best-corrected). Unpublished data and data from studies using rapid assessment methodology were later added (Stage 2).
RESULTS
Stage 1 identified 14,908 references, of which 204 articles met the inclusion criteria. Stage 2 added unpublished data from 44 rapid assessment studies and four other surveys. This resulted in a final dataset of 252 articles of 243 studies, of which 238 (98%) reported distance vision loss categories. A total of 37 studies of the final dataset reported prevalence of mild VI and four reported near VI.
CONCLUSION
We report a comprehensive systematic review of over 30 years of VI/blindness studies. While there has been an increase in population-based studies conducted in the 2000s compared to previous decades, there is limited information from certain regions (eg, Central Africa and Central and Eastern Europe, and the Caribbean and Latin America), and younger age groups, and minimal data regarding prevalence of near vision and mild distance VI.
Topics: Blindness; Global Health; Humans; Prevalence; Vision, Low; Visually Impaired Persons
PubMed: 23350553
DOI: 10.3109/09286586.2012.741279 -
Indian Journal of Ophthalmology 2012Since the year 2000, the amount written about the economics of blindness and visual impairment has increased substantially. In some cases, the studies listed under this... (Review)
Review
Since the year 2000, the amount written about the economics of blindness and visual impairment has increased substantially. In some cases, the studies listed under this heading are calculations of the costs related to vision impairment and blindness at a national or global level; in other cases the studies examine the cost-effectiveness of strategies to prevent or modify visual impairment or blindness that are intended to be applied as a guide to treatment recommendations and coverage decisions. In each case the references are just examples of many that could be cited. These important studies have helped advocates, policy makers, practitioners, educators, and others interested in eye and vision health to understand the magnitude of the impact that visual impairment and blindness have on the world, regions, nations, and individuals and the tradeoffs that need to be made to limit the impact. However, these studies only begin to tap into the insights that economic logic might offer to those interested in this field. This paper presents multiple case studies that demonstrate that the economics of blindness and visual impairment encompasses much more than simply measures of the burden of the condition. Case studies demonstrating the usefulness of economic insight include analysis of the prevention of conditions that lead to impairment, decisions about refractive error and presbyopia, decisions about disease and injury treatment, decisions about behavior among those with uncorrectable impairment, and decisions about how to regulate the market all have important economic inputs.
Topics: Blindness; Comprehensive Health Care; Cost-Benefit Analysis; Humans; Vision, Low; Visually Impaired Persons
PubMed: 22944750
DOI: 10.4103/0301-4738.100535 -
JAMA Ophthalmology Dec 2020Perceived everyday discrimination is a psychosocial stressor linked to adverse health outcomes, including mortality.
IMPORTANCE
Perceived everyday discrimination is a psychosocial stressor linked to adverse health outcomes, including mortality.
OBJECTIVE
To assess the association of vision impairment (VI), hearing impairment (HI), and dual sensory impairments (DSI) with everyday discrimination.
DESIGN, SETTING, AND PARTICIPANTS
Cross-sectional analysis of the Health and Retirement Study 2006 and 2008 surveys, a US population-based survey that included noninstitutionalized adults 51 years and older. Analyses were weighted to account for complex sample design and differential nonresponse. Data were analyzed between October 2019 and November 2019.
EXPOSURES
Participants rated their vision and hearing, using eyeglasses and/or hearing aids if applicable, on a Likert scale (poor, fair, good, very good, and excellent). Sensory impairment was defined as poor or fair ability in the relevant modality, and sensory impairment was categorized as neither sensory impairment (NSI), VI alone, HI alone, and DSI.
MAIN OUTCOMES AND MEASURES
Perceived everyday discrimination was measured on the validated 5-question Williams scale (range 0 to 5). Linear regression models estimated differences in discrimination scores by sensory categories, adjusting for age, sex, race, ethnicity, non-US birth, body mass index, relationship status, net household wealth, and number of chronic diseases (among diabetes, hypertension, heart disease, stroke, lung disease, nonskin cancer, and arthritis).
RESULTS
The sample included 13 092 individuals. After weighting the sample to be representative of the US population, 11.7% had VI alone, 13.1% HI alone, and 7.9% DSI. In the fully adjusted model, participants with VI alone (β [change in discrimination score], 0.07; 95% CI, 0.02-0.13), HI alone (β = 0.07; 95% CI, 0.02-0.11), and DSI (β = 0.23; 95% CI, 0.16-0.29) perceived greater discrimination compared with participants with NSI. The DSI group perceived greater discrimination than VI alone or HI alone.
CONCLUSIONS AND RELEVANCE
Older adults with VI or HI in the United States perceive greater everyday discrimination than older adults with NSI, and those with DSI perceive even more discrimination than those with either VI or HI alone. These results provide insight into the social impact of sensory loss and highlight a need to identify and address reasons for discrimination toward older adults with VI and HI.
Topics: Aged; Aged, 80 and over; Cross-Sectional Studies; Depressive Disorder; Discrimination, Psychological; Female; Health Surveys; Hearing Loss; Humans; Male; Middle Aged; Persons With Hearing Impairments; United States; Vision Disorders; Visually Impaired Persons
PubMed: 33034632
DOI: 10.1001/jamaophthalmol.2020.3982 -
Ophthalmology Aug 2018To estimate the prevalence of nonrefractive visual impairment and blindness in European persons 55 years of age and older. (Meta-Analysis)
Meta-Analysis Review
TOPIC
To estimate the prevalence of nonrefractive visual impairment and blindness in European persons 55 years of age and older.
CLINICAL RELEVANCE
Few visual impairment and blindness prevalence estimates are available for the European population. In addition, many of the data collected in European population-based studies currently are unpublished and have not been included in previous estimates.
METHODS
Fourteen European population-based studies participating in the European Eye Epidemiology Consortium (n = 70 723) were included. Each study provided nonrefractive visual impairment and blindness prevalence estimates stratified by age (10-year strata) and gender. Nonrefractive visual impairment and blindness were defined as best-corrected visual acuity worse than 20/60 and 20/400 in the better eye, respectively. Using random effects meta-analysis, prevalence rates were estimated according to age, gender, geographical area, and period (1991-2006 and 2007-2012). Because no data were available for Central and Eastern Europe, population projections for numbers of affected people were estimated using Eurostat population estimates for European high-income countries in 2000 and 2010.
RESULTS
The age-standardized prevalence of nonrefractive visual impairment in people 55 years of age or older decreased from 2.22% (95% confidence interval [CI], 1.34-3.10) from 1991 through 2006 to 0.92% (95% CI, 0.42-1.42) from 2007 through 2012. It strongly increased with age in both periods (up to 15.69% and 4.39% in participants 85 years of age or older from 1991 through 2006 and from 2007 through 2012, respectively). Age-standardized prevalence of visual impairment tended to be higher in women than men from 1991 through 2006 (2.67% vs. 1.88%), but not from 2007 through 2012 (0.87% vs. 0.88%). No differences were observed between northern, western, and southern regions of Europe. The projected numbers of affected older inhabitants in European high-income countries decreased from 2.5 million affected individuals in 2000 to 1.2 million in 2010. Of those, 584 000 were blind in 2000, in comparison with 170 000 who were blind in 2010.
CONCLUSIONS
Despite the increase in the European older population, our study indicated that the number of visually impaired people has decreased in European high-income countries in the last 20 years. This may be the result of major improvements in eye care and prevention, the decreasing prevalence of eye diseases, or both.
Topics: Aged; Europe; Humans; Prevalence; Vision, Low; Visual Acuity; Visually Impaired Persons
PubMed: 29548645
DOI: 10.1016/j.ophtha.2018.02.005 -
Asia-Pacific Journal of Ophthalmology... 2018
Topics: Blindness; Eye Diseases; Humans; Needs Assessment; Visually Impaired Persons
PubMed: 30207131
DOI: 10.22608/APO.2018345 -
Disability and Rehabilitation.... Nov 2022Visual sensory substitution devices (SSDs) convey visual information to a blind person through another sensory modality. Using a visual SSD in various daily activities...
PURPOSE
Visual sensory substitution devices (SSDs) convey visual information to a blind person through another sensory modality. Using a visual SSD in various daily activities requires training prior to use the device independently. Yet, there is limited literature about procedures and outcomes of the training conducted for preparing users for practical use of SSDs in daily activities.
METHODS
We trained 29 blind adults (9 with congenital and 20 with acquired blindness) in the use of a commercially available electro-tactile SSD, BrainPort. We describe a structured training protocol adapted from the previous studies, responses of participants, and we present retrospective qualitative data on the progress of participants during the training.
RESULTS
The length of the training was not a critical factor in reaching an advanced stage. Though performance in the first two sessions seems to be a good indicator of participants' ability to progress in the training protocol, there are large individual differences in how far and how fast each participant can progress in the training protocol. There are differences between congenital blind users and those blinded later in life.
CONCLUSIONS
The information on the training progression would be of interest to researchers preparing studies, and to eye care professionals, who may advise patients to use SSDs.IMPLICATIONS FOR REHABILITATIONThere are large individual differences in how far and how fast each participant can learn to use a visual-to-tactile sensory substitution device for a variety of tasks.Recognition is mainly achieved through top-down processing with prior knowledge about the possible responses. Therefore, the generalizability is still questionable.Users develop different strategies in order to succeed in training tasks.
Topics: Adult; Blindness; Humans; Retrospective Studies; Tongue; Touch; Visually Impaired Persons
PubMed: 32997554
DOI: 10.1080/17483107.2020.1821102