Search

In 2021, WHO Member States endorsed a global target of a 40-percentage-point increase in effective refractive error coverage (eREC; with a 6/12 visual acuity threshold) by 2030. This study models global and regional estimates of eREC as a baseline for the WHO initiative.The Vision Loss Expert Group analysed data from 565 448 participants of 169 population-based eye surveys conducted since 2000 to calculate eREC (met need/[met need + undermet need + unmet need]). A binary logistic regression model was used to estimate eREC by Global Burden of Disease (GBD) Study super region among adults aged 50 years and older.In 2021, distance eREC was 79·1% (95% CI 72·4-85·0) in the high-income super region; 62·1% (54·7-68·8) in north Africa and Middle East; 49·5% (45·0-54·0) in central Europe, eastern Europe, and central Asia; 40·0% (31·7-48·2) in southeast Asia, east Asia, and Oceania; 34·5% (29·4-40·0) in Latin America and the Caribbean; 9·0% (6·5-12·0) in south Asia; and 5·7% (3·1-9·0) in sub-Saharan Africa. eREC was higher in men and reduced with increasing age. Global distance eREC increased from 2000 to 2021 by 19·0%. Global near vision eREC for 2021 was 20·5% (95% CI 17·8-24·4).Over the past 20 years, distance eREC has increased in each super region yet the WHO target will require substantial improvements in quantity and quality of refractive services in particular for near vision impairment.WHO, Sightsavers, The Fred Hollows Foundation, Fondation Thea, Brien Holden Vision Institute, Lions Clubs International Foundation.

The global burden of myopia is growing. Myopia affected nearly 30% of the world population in 2020 and this number is expected to rise to 50% by 2050. This review aims to analyze the impact of myopia on individuals and society; summarizing the evidence for recent research on the prevalence of myopia and high myopia, lifetime pathological manifestations of myopia, direct health expenditure, and indirect costs such as lost productivity and reduced quality of life (QOL). The principal trends are a rising prevalence of myopia and high myopia, with a disproportionately greater increase in the prevalence of high myopia. This forecasts a future increase in vision loss due to uncorrected myopia as well as high myopia-related complications such as myopic macular degeneration. QOL is affected for those with uncorrected myopia, high myopia, or complications of high myopia. Overall the current global cost estimates related to direct health expenditure and lost productivity are in the billions. Health expenditure is greater in adults, reflecting the added costs due to myopia-related complications. Unless the current trajectory for the rising prevalence of myopia and high myopia change, the costs will continue to grow. The past few decades have seen the emergence of several novel approaches to prevent and slow myopia. Further work is needed to understand the life-long impact of myopia on an individual and the cost-effectiveness of the various novel approaches in reducing the burden.

BackgroundInformed decisions on myopia management require an understanding of financial impact. We describe methodology for estimating lifetime myopia costs, with comparison across management options, using exemplars in Australia and China.MethodsWe demonstrate a process for modelling lifetime costs of traditional myopia management (TMM=full, single-vision correction) and active myopia management (AMM) options with clinically meaningful treatment efficacy. Evidence-based, location-specific and ethnicity-specific progression data determined the likelihood of all possible refractive outcomes. Myopia care costs were collected from published sources and key informants. Refractive and ocular health decisions were based on standard clinical protocols that responded to the speed of progression, level of myopia, and associated risks of pathology and vision impairment. We used the progressions, costs, protocols and risks to estimate and compare lifetime cost of myopia under each scenario and tested the effect of 0%, 3% and 5% annual discounting, where discounting adjusts future costs to 2020 value.ResultsLow-dose atropine, antimyopia spectacles, antimyopia multifocal soft contact lenses and orthokeratology met our AMM inclusion criteria. Lifetime cost for TMM with 3% discounting was US$7437 (CI US$4953 to US$10 740) in Australia and US$8006 (CI US$3026 to US$13 707) in China. The lowest lifetime cost options with 3% discounting were antimyopia spectacles (US$7280, CI US$5246 to US$9888) in Australia and low-dose atropine (US$4453, CI US$2136 to US$9115) in China.ConclusionsFinancial investment in AMM during childhood may be balanced or exceeded across a lifetime by reduced refractive progression, simpler lenses, and reduced risk of pathology and vision loss. Our methodology can be applied to estimate cost in comparable scenarios.

ObjectivesTo determine whether a collaborative model of care that uses task-sharing for the management of low-risk diabetic retinopathy, Community Eye Care (C-EYE-C), can improve access to care and better use resources, compared with hospital-based care.DesignRetrospective audit of medical and financial records to compare two models of care.SettingA large, urban tertiary Australian publicly funded hospital.InterventionC-EYE-C is a collaborative care model, involving community-based optometrist assessment and ‘virtual review’ by ophthalmologists to manage low-risk patients. The C-EYE-C model of care was implemented from January to October 2017.ParticipantsNew low-risk patient referrals with diabetes received at a tertiary hospital ophthalmology unit.Primary and secondary outcomesHistorical standard hospital care was compared with C-EYE-C for attendance, wait-times, outcomes and costs. Clinical concordance between the optometrist and ophthalmologist diagnosis and management was assessed using weighted kappa statistic.ResultsThere were 133 new low-risk referrals, managed in standard hospital care (n=68) and C-EYE-C (n=65). Attendance rates were similar between the models of care (72.1% hospital vs 67.7% C-EYE-C, p=0.71). C-EYE-C had shorter appointment wait-time (53 vs 118 days, pConclusionThis Australian study showed that collaborative eye care resulted in reduced patient waiting times and considerable cost-savings, while maintaining a high standard of patient care compared with traditional hospital-based care in the management of low-risk hospital referrals with diabetic eye disease. The improved access and reduced costs were largely the result of better task allocation through greater utilisation of primary eye care professionals to provide services for low-risk patients. Better resource use may free up further resources for other eye care services.

Background: The Vision Loss Expert Group and Global Burden of Disease Study have extensively updated estimates of global vision loss burden in 2020, temporal changeover 3 decades and forecasts for 2050. Methods: A systematic review and meta-analysis was conducted of population-based datasets relevant to vision impairment (VI) from January 1980 to October 2018. Hierarchical models were fitted to estimate 2020 prevalence (with 95% uncertainty intervals, UI) of (1) mild VI (presenting visual acuity [PVA] 6/12). Findings: In 2020, an estimated 43.2 million (95% UI: 37.5-48.2 million; 55% female) people were blind, 295.3 (95% UI 267.0-325.5) million had MSVI, 257.3 (95% UI 232.2-284.7) million had mild VI, and 507.4 million (95% UI 369.3–663.8) were VI from uncorrected presbyopia. Globally among adults aged ≥50 years, age-standardised prevalence of blindness reduced by 29% between 1990 and 2020, while MSVI increased slightly (+2.4%). The number of blind people increased by 50.2% and MSVI by 91.6%. By 2050, we predict 895.5 million people blind/VI. Interpretation: It is encouraging that age-adjusted prevalence of blindness has reduced over the past 3 decades, yet due to population growth progress is not keeping pace with needs. We face enormous challenges in avoiding vision impairment as the global population grows and ages. Funding Statement: Brien Holden Vision Institute. Fondation Thea. Fred Hollows Foundation. Gates Foundation. Sightsavers International. University of Heidelberg. Declaration of Interests: A.M. Bron, Allergan (C) Baush and Lomb (C), Santen (C), Thea (C) - (C) stands for consultant. J Kempen: Consultant (DSMC Chair) for Gilead. Grants and contracts from National Institutes of Health/National Eye Institute; Sight for Souls; and Christoffel Blindenmission. No other authors had conflicts to declare.

Background Since the introduction of Silicone hydrogel (SiHy) contact lenses 20 years ago, industry has continued to modify lens materials, designs, lens care products and manufacturing processes, striving to improve contact lens physiological performance, comfort, and convenience for wearers. The purpose of this study was to investigate whether the ocular health of habitual soft contact lens wearers today is better than it was in previous decades. Methods Baseline ocular physiology data for 3624 participants from a The Brien Holden Vision Institute clinical trials database were retrospectively reviewed. Records were grouped into 3 time periods; A: >2 decades ago (1997–1999), B: one decade ago (2009–2014) and C: recent years (since 2015). Physiology data for both neophytes and habitual contact lens wearers included; bulbar, limbal and upper palpebral conjunctival redness, corneal and conjunctival staining and conjunctival indentation from contact lenses. Results Corneal staining levels are similar between neophytes and contact lens wearers at time points A and C but worse for contact lens wearers at time point B. Limbal redness was greater in contact lens wearers than in neophytes at time point A but at time points B and C they are not different to the non-contact lens wearing population. In recent years, most ocular physiological variables in habitual contact lens wearers are similar to neophytes. Conclusions While there have been changes over the past two decades in ocular physiological responses to contact lens wear, it appears that ocular health with current day contact lens wear is similar to no lens wear in most respects.

Topic Presbyopia prevalence and spectacle-correction coverage were estimated by systematic review and meta-analysis of epidemiologic evidence, then modeled to expand to country, region, and global estimates. Clinical Relevance Understanding presbyopia epidemiologic factors and correction coverage is critical to overcoming the burden of vision impairment (VI) from uncorrected presbyopia. Methods We performed systematic reviews of presbyopia prevalence and spectacle-correction coverage. Accepted presbyopia prevalence data were gathered into 5-year age groups from 0 to 90 years or older and meta-analyzed within World Health Organization global burden of disease regions. We developed a model based on amplitude of accommodation adjusted for myopia rates to match the regionally meta-analyzed presbyopia prevalence. Presbyopia spectacle-correction coverage was analyzed against country-level variables from the year of data collection; variation in correction coverage was described best by a model based on the Human Development Index, Gini coefficient, and health expenditure, with adjustments for age and urbanization. We used the models to estimate presbyopia prevalence and spectacle-correction coverage in each age group in urban and rural areas of every country in the world, and combined with population data to estimate the number of people with near VI. Results We estimate there were 1.8 billion people (prevalence, 25%; 95% confidence interval [CI], 1.7–2.0 billion [23%–27%]) globally with presbyopia in 2015, 826 million (95% CI, 686–960 million) of whom had near VI because they had no, or inadequate, vision correction. Global unmet need for presbyopia correction in 2015 is estimated to be 45% (95% CI, 41%–49%). People with presbyopia are more likely to have adequate optical correction if they live in an urban area of a more developed country with higher health expenditure and lower inequality. Conclusions There is a significant burden of VI from uncorrected presbyopia, with the greatest burden in rural areas of low-resource countries.

BackgroundTo assess prevalence and causes of vision loss in Central and South Asia.MethodsA systematic review of medical literature assessed the prevalence of blindness (presenting visual acuityResultsIn Central and South Asia combined, age-standardised prevalences of blindness, MSVI and MVI in 2015 were for men and women aged 50+years, 3.72% (80% uncertainty interval (UI): 1.39–6.75) and 4.00% (80% UI: 1.41–7.39), 16.33% (80% UI: 8.55–25.47) and 17.65% (80% UI: 9.00–27.62), 11.70% (80% UI: 4.70–20.32) and 12.25% (80% UI:4.86–21.30), respectively, with a significant decrease in the study period for both gender. In South Asia in 2015, 11.76 million individuals (32.65% of the global blindness figure) were blind and 61.19 million individuals (28.3% of the global total) had MSVI. From 1990 to 2015, cataract (accounting for 36.58% of all cases with blindness in 2015) was the most common cause of blindness, followed by undercorrected refractive error (36.43%), glaucoma (5.81%), age-related macular degeneration (2.44%), corneal diseases (2.43%), diabetic retinopathy (0.16%) and trachoma (0.04%). For MSVI in South Asia 2015, most common causes were undercorrected refractive error (accounting for 66.39% of all cases with MSVI), followed by cataract (23.62%), age-related macular degeneration (1.31%) and glaucoma (1.09%).ConclusionsOne-third of the global blind resided in South Asia in 2015, although the age-standardised prevalence of blindness and MSVI decreased significantly between 1990 and 2015.

BackgroundTo assess prevalence and causes of vision impairment in South-east Asia and Oceania regions from 1990 to 2015 and to forecast the figures for 2020.MethodsBased on a systematic review of medical literature, prevalence of blindness (presenting visual acuity (PVA) N5 or N8 in the presence of normal vision) were estimated for 1990, 2010, 2015 and 2020.ResultsThe age-standardised prevalence of blindness for all ages and both genders was higher in the Oceania region but lower for MSVI when comparing the subregions. The prevalence of near vision impairment in people≥50 years was 41% (uncertainty interval (UI) 18.8 to 65.9). Comparison of the data for 2015 with 2020 predicts a small increase in the numbers of people affected by blindness, MSVI and mild VI in both subregions. The numbers predicted for near VI in South-east Asia are from 90.68 million in 2015 to 102.88 million in 2020. The main causes of blindness and MSVI in both subregions in 2015 were cataract, uncorrected refractive error, glaucoma, corneal disease and age-related macular degeneration. There was no trachoma in Oceania from 1990 and decreasing prevalence in South-east Asia with elimination predicted by 2020.ConclusionsIn both regions, the main challenges for eye care come from cataract which remains the main cause of blindness with uncorrected refractive error the main cause of MSVI. The trend between 1990 and 2015 is for a lower prevalence of blindness and MSVI in both regions.

BackgroundWithin a surveillance of the prevalence and causes of vision impairment in high-income regions and Central/Eastern Europe, we update figures through 2015 and forecast expected values in 2020.MethodsBased on a systematic review of medical literature, prevalence of blindness, moderate and severe vision impairment (MSVI), mild vision impairment and presbyopia was estimated for 1990, 2010, 2015, and 2020.ResultsAge-standardised prevalence of blindness and MSVI for all ages decreased from 1990 to 2015 from 0.26% (0.10–0.46) to 0.15% (0.06–0.26) and from 1.74% (0.76–2.94) to 1.27% (0.55–2.17), respectively. In 2015, the number of individuals affected by blindness, MSVI and mild vision impairment ranged from 70 000, 630 000 and 610 000, respectively, in Australasia to 980 000, 7.46 million and 7.25 million, respectively, in North America and 1.16 million, 9.61 million and 9.47 million, respectively, in Western Europe. In 2015, cataract was the most common cause for blindness, followed by age-related macular degeneration (AMD), glaucoma, uncorrected refractive error, diabetic retinopathy and cornea-related disorders, with declining burden from cataract and AMD over time. Uncorrected refractive error was the leading cause of MSVI.ConclusionsWhile continuing to advance control of cataract and AMD as the leading causes of blindness remains a high priority, overcoming barriers to uptake of refractive error services would address approximately half of the MSVI burden. New data on burden of presbyopia identify this entity as an important public health problem in this population. Additional research on better treatments, better implementation with existing tools and ongoing surveillance of the problem is needed.

Presbyopia prevalence and spectacle-correction coverage were estimated by systematic review and meta-analysis of epidemiologic evidence, then modeled to expand to country, region, and global estimates.Understanding presbyopia epidemiologic factors and correction coverage is critical to overcoming the burden of vision impairment (VI) from uncorrected presbyopia.We performed systematic reviews of presbyopia prevalence and spectacle-correction coverage. Accepted presbyopia prevalence data were gathered into 5-year age groups from 0 to 90 years or older and meta-analyzed within World Health Organization global burden of disease regions. We developed a model based on amplitude of accommodation adjusted for myopia rates to match the regionally meta-analyzed presbyopia prevalence. Presbyopia spectacle-correction coverage was analyzed against country-level variables from the year of data collection; variation in correction coverage was described best by a model based on the Human Development Index, Gini coefficient, and health expenditure, with adjustments for age and urbanization. We used the models to estimate presbyopia prevalence and spectacle-correction coverage in each age group in urban and rural areas of every country in the world, and combined with population data to estimate the number of people with near VI.We estimate there were 1.8 billion people (prevalence, 25%; 95% confidence interval [CI], 1.7-2.0 billion [23%-27%]) globally with presbyopia in 2015, 826 million (95% CI, 686-960 million) of whom had near VI because they had no, or inadequate, vision correction. Global unmet need for presbyopia correction in 2015 is estimated to be 45% (95% CI, 41%-49%). People with presbyopia are more likely to have adequate optical correction if they live in an urban area of a more developed country with higher health expenditure and lower inequality.There is a significant burden of VI from uncorrected presbyopia, with the greatest burden in rural areas of low-resource countries.

PubMed: 28779882, Background Global and regional prevalence estimates for blindness and vision impairment are important for the development of public health policies. We aimed to provide global estimates, trends, and projections of global blindness and vision impairment. Methods We did a systematic review and meta-analysis of population-based datasets relevant to global vision impairment and blindness that were published between 1980 and 2015. We fitted hierarchical models to estimate the prevalence (by age, country, and sex), in 2015, of mild visual impairment (presenting visual acuity worse than 6/12 to 6/18 inclusive), moderate to severe visual impairment (presenting visual acuity worse than 6/18 to 3/60 inclusive), blindness (presenting visual acuity worse than 3/60), and functional presbyopia (defined as presenting near vision worse than N6 or N8 at 40 cm when best-corrected distance visual acuity was better than 6/12). Findings Globally, of the 7·33 billion people alive in 2015, an estimated 36·0 million (80% uncertainty interval [UI] 12·9–65·4) were blind (crude prevalence 0·48%; 80% UI 0·17–0·87; 56% female), 216·6 million (80% UI 98·5–359·1) people had moderate to severe visual impairment (2·95%, 80% UI 1·34–4·89; 55% female), and 188·5 million (80% UI 64·5–350·2) had mild visual impairment (2·57%, 80% UI 0·88–4·77; 54% female). Functional presbyopia affected an estimated 1094·7 million (80% UI 581·1–1686·5) people aged 35 years and older, with 666·7 million (80% UI 364·9–997·6) being aged 50 years or older. The estimated number of blind people increased by 17·6%, from 30·6 million (80% UI 9·9–57·3) in 1990 to 36·0 million (80% UI 12·9–65·4) in 2015. This change was attributable to three factors, namely an increase because of population growth (38·4%), population ageing after accounting for population growth (34·6%), and reduction in age-specific prevalence (?36·7%). The number of people with moderate and severe visual impairment also increased, from 159·9 million (80% UI 68·3–270·0) in 1990 to 216·6 million (80% UI 98·5–359·1) in 2015. Interpretation There is an ongoing reduction in the age-standardised prevalence of blindness and visual impairment, yet the growth and ageing of the world's population is causing a substantial increase in number of people affected. These observations, plus a very large contribution from uncorrected presbyopia, highlight the need to scale up vision impairment alleviation efforts at all levels. Funding Brien Holden Vision Institute. © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license

Purpose To investigate utility (a preference-based quality of life [QoL] measure) associated with uncorrected refractive error (URE). Design Cross-sectional study. Participants A cohort of 341 consecutive patients 40 to 65 years of age with refractive error and no ocular disease impairing vision worse than 20/25 (0.1 logarithm of the minimum angle of resolution [logMAR] units) in the better eye. Without vision correction, 30 had no vision impairment, 65 had only distance vision impairment (DVI), 97 had only near vision impairment (NVI), 112 had moderate amounts of both distance and near vision impairment (DNVI), and 37 had severe impairment (distance or near worse than 20/200 [>1.0 logMAR]) in the better eye. Methods All participants underwent a comprehensive eye examination with refraction, aided and unaided visual acuity (VA) at 6 m and 40 cm, and ocular health assessment. Utilities were elicited for a number of scenarios using a standardized, face-to-face time trade-off (TTO) interview method. Main Outcome Measures The main outcome measure was TTO utility for the participant's own uncorrected vision state. Utilities ranged from 0 to 1, where 0 = death and 1 = perfect vision, and were scaled to account for comorbidities so that 1 = perfect health (adjusted utility). Results Unaided VA was 0.50±0.24 logMAR at distance in the DVI group, 0.43±0.17 logMAR at near in the NVI group, and 0.72±0.36 and 0.56±0.29 at distance and near, respectively, in the DNVI group. Adjusted utilities for the 3 groups were 0.82±0.16 in the DVI group, 0.81±0.17 in the NVI group, and 0.68±0.25 in the DNVI group. The DVI and NVI group utilities (adjusted and unadjusted) did not differ significantly ( P = 0.73 and P = 0.77, respectively). The DNVI utility was significantly worse than that of the DVI and NVI groups (adjusted and unadjusted, P Conclusions The URE is associated with measurable reductions in utility (and therefore QoL). Reductions are similar regardless of whether near or distance vision is impaired, but worse when both are impaired. The results underscore the significance of the effect of URE on QoL, particularly with respect to uncorrected presbyopia, which has been a relatively neglected area in research and policy. The utility figures in this study can be used as inputs for cost-effectiveness studies relating to URE to assist resource allocation decisions. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Background: The 2004 tsunami focused unprecedented international aid and resources on Sri Lanka. Among other responses, a program delivered by volunteer optometrists enabled many local people to a...

Purpose Anecdotal reports suggest that steeply fitted rigid contact lenses can induce corneal steepening and myopic shifts in refraction. This study investigated changes in corneal topography, corneal thickness, and refraction after short-term wear of apical clearance lenses. Methods : Ten young adults participated in the study in which apical clearance lenses (Conoid, Hydron Pty. Ltd., Frenchs Forest, NSW, Australia), fitted approximately 0.3 mm steeper than the flattest keratometric reading, were worn for 4 h. A polymethyl methacrylate (PMMA) lens was worn in one eye, and a Boston XO lens (Bausch & Lomb, Rochester, NY) was worn in the other. Lenses were nonfenestrated in the first trial, and a single midperipheral fenestration was incorporated for a second trial. Corneal topography was monitored using the EyeSys topographic analysis system (EyeSys Vision, Inc., Houston, TX); central corneal thickness was quantified using ultrasonic pachometry; and refraction and anterior ocular response were also monitored. Results Significant central corneal edema (8.2 +/- 2.2%) was demonstrated in the PMMA lens-wearing eye only. Fenestration did not reduce the edema response. We found significant corneal steepening over a 5- to 6-mm central zone, which was more pronounced in the PMMA lens-wearing eye and was modified by lens fenestration. The curvature changes altered central corneal shape from prolate (Q = -0.06 +/- 0.10) to oblate (Q = -0.26 +/- 0.31). A slight myopic shift in refraction (-0.38 +/- 0.60 D) was found with the PMMA lenses only. Conclusions : Apical clearance lenses induce corneal steepening after short-term wear. Although corneal molding is implicated as the primary factor driving the shape change, corneal edema and postlens tear film pressures can modify this response.

To investigate the manner in which contemporary soft contact lenses differ in the distribution of optical power within their optic zones and establish if these variations affect the vision of wearers or the prescribing procedure for back vertex power (BVP).By using a Visionix VC 2001 contact lens power analyzer, power profiles were measured across the optic zones of the following contemporary contact lenses ACUVUE 2, ACUVUE ADVANCE, O2OPTIX, NIGHTDAY and PureVision. Single BVP measures were obtained using a Nikon projection lensometer. Visual performance was assessed in 28 masked subjects who wore each lens type in random order. Measurements taken were high and low contrast visual acuity in normal illumination (250 Cd/m), high contrast acuity in reduced illumination (5 Cd/m), subjective visual quality using a numerical rating scale, and visual satisfaction rating using a Likert scale.Marked differences in the distribution of optical power across the optic zone were evident among the lens types. No significant differences were found for any of the visual performance variables (p0.05, analysis of variance with repeated measures and Friedman test).Variations in power profile between contemporary soft lens types exist but do not, in general, result in measurable visual performance differences in the short term, nor do they substantially influence the BVP required for optimal correction.

The 2004 tsunami focused unprecedented international aid and resources on Sri Lanka. Among other responses, a program delivered by volunteer optometrists enabled many local people to access eye examinations and spectacles for the first time. The data collected from the eye-care delivery program during 2005 are summarised in this report, as an evidence base for planning future eye-care interventions in these provinces or similar areas.A total of 96 eye clinics were conducted by visiting volunteer optometrists in the northern and eastern provinces of Sri Lanka, at which 20,090 people were examined. Clinical records were reviewed for conditions causing visual impairment, conditions that could cause impaired vision in future if left untreated, eye-care outcomes and barriers to seeking care.Complete records were available for 14,669 people. Seventy-nine per cent of this clinical population had never had an eye examination. Uncorrected refractive error including presbyopia caused visual impairment for 78 per cent (11,388) of people who presented for an eye examination. Cataract caused impaired vision for 15 per cent (2,180) of people and was the main reason for referral beyond primary eye-care, although only five per cent (695) of people presenting were referred for cataract surgery, as local capacity constraints set a visual acuity requirement of 6/36 or worse. The gender and age profiles of people attending the clinics were not consistent with equitable blindness prevention.The high proportion of people who had not previously had an eye examination, particularly those with significant uncorrected refractive error, provides evidence for the acute need for further development and support of community-level eye-care services in the regions visited. Women and older people should be targeted by future programs to achieve equity of blindness prevention.

Purpose. The efficacy of overnight wear of four types of reverse-geometry lenses was compared. The length of time needed to achieve correction and any adverse events that occurred during the course of the study were recorded. Methods. In this prospective, randomized study, 60 subjects (18 to 35 years old) with refractive error between -1.00 to -4.00 D (cyl ≤ -1.50) wore reverse-geometry lenses overnight only. All subjects were assigned a Rinehart Reeves lens in one eye, and subsets of 20 subjects were randomly assigned a Mountford BE, DreimLens, or Contex D Series 4 lens for the contralateral eye. Visits included baseline, dispensing, 1 day, 1 week, and 1 month. Biomicroscopy, unaided visual acuity, subjective refraction, best-corrected visual acuity at high and low contrast and high and low illumination, corneal topography, and subjective rating data were collected. Results. Forty-six subjects completed the study. At 1 month, there were no significant differences between lens types in their effect on unaided visual acuity, subjective sphere, subjective cylinder, best-corrected visual acuity at high and low contrast at high illumination and low contrast at low illumination, apical corneal radius, corneal eccentricity, and subjective ratings. Between 1 week and 1 month, there was a significant improvement in subjective ratings of quality of day and night vision (p < 0.05) but no significant change in the objective measures. No significant ocular adverse events were observed during the trial. Conclusions. The lens types tested were all similarly effective in the reduction of myopic refractive error. Subjective ratings continued to improve after objective measures stabilized at 1 week. Overnight lens wear proceeded for 1 month without significant adverse reactions.