视功能损害眼病患者生存质量量表的研究

目的研究一个适合测量我国视功能损害眼病患者的生存质量量表。方法通过指标筛选，最终选择２０个指标形成生存质量量表。应用该量表测量了５７例单纯视力损害的白内障患者和６０例有不同程度视力及视野损害的青光眼患者，并对该量表进行效度、信度和反应性的评价。结果该量表２０个指标，包括症状、视功能、身体机能、社会活动及精神心理等四个方面。（１）准则关联效度：ｒ＝０．６８６５，Ｐ＝０．０００。（２）重测信度：ｒ＝０．８９５９，Ｐ＝０．０００；克朗巴赫系数：α＝０．９３５８；方差比＝０．０５５１；分半信度：Ｒ＝０．９５５３。（３）反应度：ｔ检验＝５．９５（Ｐ＝０．０００），效应大小统计量为１．５３３。结论该量表具有满意的效度、信度和反应度。可试用于临床试验评价     

新疆库车县维吾尔族农民白内障手术的生存质量评价

目的评价新疆库车县年龄≥40岁维吾尔族农民白内障术后患者的主观视功能（visual function,VF）和生存质量（quality of life,QOL）。方法在整群随机抽样的2955人中,所有白内障术后患者作为手术组,部分视力正常者（双眼视力均〉0.3,每10例中按序抽取1例受检者）和视功能损害者（1只眼视力〈0.1,每3例中按序抽取1例受检者）作为对照组。该两组均接受眼科检查并由专人进行问卷调查。结果在受检的2955人中,手术组64人中62人完成问卷;对照组中,正常对照1920人中的145人和视功能损害971人中的230人完成问卷调查。手术组与对照组的VF平均得分分别为77.1和68.8;手术组与对照组的QOL平均得分分别为89.1和91.7;非手术组视力分级与VF和QOL得分的相关性高于手术组;经多因素回归分析校正了年龄、性别、文化、视力分级后,手术组与对照组的VF得分和QOL得分差异有统计学意义（两者P〈0.001）.经偏回归系数t检验,影响手术组与对照组的主要因素均为视力,其标准化偏回归系数分别为-0.731和-0.610。结论新疆库车县维吾尔族农民白内障术后VF和QOL得分无明显提高,影响的主要因素为视力。故如何切实提高白内障患者的视力是提高生存质量的重点。     

视网膜脱离复位后视功能研究

目的 研究视网膜脱离（ＲＤ）术后视功能的恢复及其影响因素。方法 选择孔源性ＲＤ痊愈病例２３３例（２３８眼）,采用Ｘ＾２检验进行统计分析。结果 术前３６．７％患者视力≥０．１,而术后为８１．４％（Ｐ〈０．０１）;术前黄斑不脱离和脱离１周内的患者术后视力１００．０％≥０．３,脱离１周后只有２７．１％的患者有相应的视力;术前视力与术后视力明显相关（r＝０．５１７,Ｐ〈０．０１）。结论 ＲＤ术后视力得到不     

青光眼患者的生存质量及其影响因素研究

目的：评价青光眼患者的生存质量并探讨影响其生存质量的因素。 方法：采用国家眼科研究所视功能问卷-25,对126例青光眼患者的生活质量进行评价。 结果：青光眼患者的生存质量普遍下降,不同程度的视力损害明显影响着患者的生存质量得分（P＜0.01）。多因素逐步直线回归显示：生存质量的得分与年龄、经济收入、遵医行为有密切关系（P＜0.05）。 结论：在保护青光眼患者视功能的同时,要重视其社会、心理等因素,给予其必要的健康教育和心理辅导,以期提高其生存质量。     

多焦点人工晶状体和单焦点非球面人工晶状体植入术后患者视功能及生存质量比较

目的　比较植入多焦点人工晶状体（ｉｎｔｒａｏｃｕｌａｒｌｅｎｓ,ＩＯＬ）和单焦点非球面ＩＯＬ对单纯白内障患者术后视功能及生存质量的影响。方法　采用前瞻性和回顾性调查研究,共纳入７２例（１４４眼）老年性白内障患者,均行超声乳化联合ＩＯＬ植入术,其中２０例植入折叠式多焦点ＩＯＬ（多焦点ＩＯＬ组）,５２例植入折叠式单焦点非球面ＩＯＬ（单焦点ＩＯＬ组）,问卷调查并比较患者术前和术后６个月的视功能及生存质量。结果　术后两组患者总体视功能及生存质量之间的差异均无统计学意义（均为Ｐ＞０．０５）,但较术前均有提高,差异均有统计学意义（均为Ｐ＜０．０５）。在活动能力、社会交际能力和心理健康方面,单焦点非球面ＩＯＬ植入后却表现出较为明显的优势,差异均有统计学意义（均为Ｐ＜０．０５）;多焦点ＩＯＬ的术后脱镜率明显高于单焦点非球面ＩＯＬ（Ｐ＜０．０５）;而在术后视功能、生存质量的其他具体方面（与视力有关的日常活动限制、周边视野、感觉适应、立体觉和自理能力）,两组之间的差异均无统计学意义（均为Ｐ＞０．０５）。结论　单焦点ＩＯＬ和多焦点ＩＯＬ在改变视功能和生存质量方面总体效果相同,但多焦点ＩＯＬ在患者脱镜方面有明显优势,而单焦晶状体在价格上表现出比较明显的优势。     

渗出型老年黄斑变性40例随访观察

为探讨渗出型老年黄斑变性（ＡＭＤ）的病灶损害和视功能改变的发展特征，用视力、眼底彩照和荧光血管造影（ＦＦＡ）、明视视网膜电图（ＥＲＧ）、ＦＭ１００—ｈｕｅ色彩试验分别对４８只、２４只、３５只及１４只渗出型ＡＭＤ患眼进行了随访检测。结果：渗出型ＡＭＤ的病灶损害发展快慢不一，但６５岁以上组，其病灶发展速率比６５岁以下组的要快些（Ｐ＜０．０５）。在平均３３．２个月的随访过程中，有７５．０％的患眼随访终了时的视力在０．１或以下。明视ＥＲＧ和ＦＭ１００—ｈｕｅ色彩试验在随访前后无明显变化。结论：６５岁以上的渗出型ＡＭＤ患者，其病灶损害一般发展较快，大部分患眼在随访终了时视力在０．１或以下。     

白内障患者视功能损害和生存质量分析

目的:观察白内障患者视功能损害生存质量下降情况。方法:应用视功能损害患者生存质量量表对不同视力损害的256例双眼白内障患者进行测量分析。结果:白内障患者生存质量总分以及各指标分数下降。重度视力下降组生存质量分数下降更加明显。结论:白内障患者由于视功能下降而生存质量受损害。生存质量的研究使医师更加全面了解患者的需求。     

中心性浆液性脉络膜视网膜病变荧光造影与视力关系

目的：探讨中心性浆液性脉络膜视网膜病变患者的眼底荧光血管造影的改变与视力关系。方法：用日本Ｔｏｐｃｏｎ眼底照相机对１２１例中浆患者进行眼底荧光血管造影，并结合临床进行分析。结果：渗漏点位置≤１／３ＰＤ，视力≤０．５为１３只眼（５０％），视力＞０．５为１３只眼（５０％）；渗漏点位置＞１／３ＰＤ，视力≤０．５为１２只眼（２５．５％），视力＞０．５为３５只眼（７４．５％），两项之比，差异有显著性意义（Ｐ＜０．０５）。同时，渗漏面积≤１／３ＰＤ，视力≤０．５为５只眼（１４．３％），视力＞０．５为３０只眼（８５．７％）；渗漏面积＞１／３ＰＤ，视力≤０．５为１９只眼（５０％），视力＞０．５为１９只眼（５０％），两项之比，差异有极显著意义（Ｐ＜０．００１）。又有二例，渗漏点在黄斑中心凹，视力为１．５。结论：渗漏面积大小与视力预后有密切关系，渗漏部位与视力预后有一定关系。个别病人渗漏点位于黄斑中心凹，却可能保持正常视功能     

中国山西334例“百万贫困白内障患者复明工程”手术效果分析

目的：了解中国山西省贫困白内障患者术后视力、视功能和生存质量的变化,分析贫困白内障患者手术成本／效果。方法：采用回顾性方法,对334例334眼接受贫困白内障复明手术的患者进行基本情况、术前及术后1 wk视力、术中并发症、术后并发症的病历采集及现场调查,对其中83例进行视功能和生存质量调查,225例贫困白内障患者和120例非贫困白内障患者进行手术成本／效果的对比分析,使用多重线性回归模型及 Logistic回归模型进行术后视力影响因素分析。结果：患者术后1 wk视力明显高于术前视力（ P＜0．05）,其中术后1 wk视力≥0．5的为235例（70．4％）、视力＜0．05的为16例（4．8％）。多重线性回归分析显示,眼部其他疾病、白内障分类是术后视力的影响因素。 logistic回归分析显示,术前视力低、眼部有其他疾病是术后低视力的危险因素,其OR值及其95％CI依次为6．5（2．8－14．8）和1．3（1．0－1．6）。术后视功能以及生存质量均高于术前。贫困白内障患者手术成本／效果低于非贫困白内障。结论：贫困白内障患者术后视力、视功能明显提高,且手术成本低,显著改善了生活质量。     

100例中心性浆液性脉络膜视网膜病变的立体视觉

目的：探讨中浆患者立体视功能状况及影响因素。方法：常规检查１００例患者（１０３只眼）的视力、屈光、Ａｍｓｌｅｒ方格卡、眼底及眼底荧光血管造影，采用刘蔼年《双眼影像不等检查图》检测双眼影像，使用颜少明《立体视觉检查图》检查中心暗点及立体视功能。结果：１６例（１６．０％）患者三项立体视功能正常，其识别响应时间延长；８４例（８０．０％）患者有程度不同的立体视功能异常，其受损程度与视力的降低、中心暗点大小及双眼影像差大小有关。结论：中浆患者多出现立体视功能损害，临床评估患者视功能损害时应全面考虑。     

广东省斗门县白内障手术的生存质量评价

目的：评价广东省斗门县年龄≥50岁人群中白内障术后患者的主观视功能（visual function,VF）和生存质量（quality of life,QOL）。方法：整群抽样法确定样本人群,其中白内障术后患者组成手术组,视功能损害者（1只眼视力＜0．1者）和部分正常对照者（双眼视力均＜＞0．3者）组成非手术组,由4位工作人员按照标准化方式完成VF和QOL问卷调查工作。结果：在5342例受检查中,手术组109例白内障术后患者中99例,非手术组626例视功能损害者中535例、3227例正常对照者中119例完成问卷调查工作。随着视力自正常下降至严重盲,非手术组VF和QOL分数的中位数分别自92下降至2和自100下降至19;手术组VF和QOL分数的中位数分别自80下降至8和自90下降至31。手术组视力与VF和QOL分数的关系与非手术组相似。VF和QOL的总分数手术组分别为40和56,非手术组分别为56和72。通过多因素回归分析校正视力、年龄、性别和教育程度后,非手术组和手术组的QOL分数差异有显著意义（P＝0．015）,VF分数差异无显著意义（P＝0．199）。结论：VF和QOL与视力显著相关。在本研究人群中,白内障术后患者的主观VF和QOL无明显提高,临床应进一步重视白内障术后患者的随访工作和社会心理康复。     

Visual acuity and quality of life outcomes in cataract surgery patients in Hong Kong.

BACKGROUND: Visual acuity, visual functioning, and vision related quality of life outcomes after cataract surgery were assessed in a population based study in a suburban area of Hong Kong. METHODS: A cluster sampling design was used to select apartment buildings within housing estates for enumeration. All enumerated residents 60 years of age or over were invited for an eye examination and visual acuity measurement at a site within each estate. Visual functioning (VF) and vision related quality of life (QOL) questionnaires were administered to interview subjects who had undergone cataract surgery and to unoperated people with presenting visual acuity less than 6/60 in either eye, and a sample of those with normal visual acuity. RESULTS: 36.6% of the 310 cataract operated individuals had presenting visual acuity 6/18 or better in both eyes, and 40.0% when measured by pinhole. 4.5% were blind, with presenting visual acuity less than 6/60 in both eyes. Of operated eyes, 59.6% presented with visual acuity 6/18 or better. 11.2% of the operated eyes were blind with vision less than 6/60. Visual acuity outcomes 6/18 or better were marginally associated with surgery in private versus public hospitals. Lens status (pseudophakic versus aphakic) and surgical period (within the most recent 3 years versus before) were not significantly related to vision outcomes. Mean VF and QOL scores decreased consistently with decreasing vision status. Spearman correlation with vision status was 0.420 for VF scores and 0.313 for QOL scores. Among VF/QOL subscales, correlation was strongest for visual perception (r = 0.447) among VF subscales and weakest for self care (r = 0.171) among QOL subscales. Regression adjusted VF and QOL total scores for cataract operated individuals were slightly lower than for those of visually comparable unoperated individuals (p<0.05). CONCLUSIONS: Cataract operations in Hong Kong did not consistently produce good presenting visual acuity outcomes, suggesting that postoperative monitoring would be useful to minimise visual impairment in this population. Although vision outcomes were consistently correlated with all VF/QOL subscale scores, there was a differential impact with VF subscales usually being affected more by reduced acuity than the more general QOL subscales.     

Visual acuity and quality of life in patients with cataract in Doumen County, China.

PURPOSE: To evaluate the effectiveness of cataract surgery in achieving sight restoration and vision-related quality-of-life (QOL) in patients from rural southern China. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: A total of 109 cataract operated persons (152 eyes) and 654 unoperated persons. METHODS: Cluster sampling was used in identifying a random sample of 5342 persons 50 years of age and older for visual acuity and eye examinations. Visual functioning (VF) and QOL questionnaires were administered to aphakic and pseudophakic individuals, unoperated persons with presenting visual acuity less than 0.10 in either eye, and a sample of those with normal vision. MAIN OUTCOME MEASURES: Distance visual acuity, VF, and QOL questionnaire scores. RESULTS: Among the cataract operated participants, 43 (39.4%) were bilaterally operated on, 32.1% had presenting visual acuity less than 0.10 in both eyes with 8.3% greater than or equal to 0.32 in both eyes. Of operated eyes, 52.6% presented with visual acuity less than 0.10, 23.7% greater than or equal to 0.32; with best correction, the corresponding percentages were 21.1% and 42.1%. Uncorrectable aphakia due to surgical complications was common. In a multivariate regression model, better visual acuity outcomes were associated with higher level surgeon practice settings and recent surgery. On a 0 to 100 scale, mean VF and QOL scores for the cataract operated population were 41.6 and 54.5, respectively. Mean scores ranged from 84.4 and 93.4, respectively, for the unoperated persons with normal vision, to 14.6 and 31.2, respectively, for those with visual acuity less than 0.05 in both eyes. The VF and QOL scores were closely correlated with presenting visual acuity in both cataract operated and unoperated populations (r = 0.49-0.64). Scores among the cataract operated population were not influenced by age, gender, or education level. Among the unoperated population, lack of education was associated with lower VF and QOL scores (P = 0.017 and P = 0.005, respectively), and older age was associated with lower QOL scores (P < 0.001). CONCLUSION: Patients in rural southern China are not realizing the full sight-restoring potential of modern-day cataract surgery. Remedial efforts are needed to improve the performance of local eye surgeons.     

Visual functioning and quality of life outcomes among cataract operated and unoperated blind populations in Nepal

BACKGROUND—Visual acuity and vision related quality of life outcomes in cataract surgery were evaluated in a population based survey in two geographic zones in Nepal.
METHODS—Case finding was based on random sampling using a stratified cluster design with door to door enumeration of people aged 45 years followed by eye examinations at village sites. All aphakics/pseudophakics, those with visual acuity less than 6/60 in either eye, and a sample of those with normal visual acuity were administered visual functioning (VF) and quality of life (QOL) questionnaires.
RESULTS—15% of the 159 cataract operated cases had presenting visual acuity 6/18 in both eyes, 38% with best corrected visual acuity. 21% were still blind with presenting visual acuity <6/60 in both eyes, 7% with best correction. On a 0-100 scale, mean VF and QOL scores were 87.2 and 93.9 respectively in normally sighted unoperated individuals, dropping to 15.6 and 29.5 for those severely blind (<3/60). Among the cataract operated, mean VF and QOL scores were 47.5 and 55.4, respectively. VF and QOL scores correlated with vision status at statistically significant levels (p <0.0001)
CONCLUSION—Cataract surgery outcomes, whether measured by traditional visual acuity or by patient reported VF/QOL, are at levels many would consider unacceptably low. It is apparent that in the quest to reduce cataract blindness much more attention must be given to improving surgery outcomes.

Keywords: cataract surgery; visual acuity; visual functioning; quality of life     

Impact of impaired vision and eye disease on quality of life in Andhra Pradesh

PURPOSE: To determine the impact of visual impairment and eye diseases on quality of life (QOL) in an older population of Andhra Pradesh in southern India. METHODS: The World Health Organization (WHO) QOL (WHOQOL) instrument was adapted as a health-related quality of life (HRQOL) instrument for administration to adults participating in the Andhra Pradesh Eye Disease Study. Participants aged 40 years and older (n = 3702), 99.4% of the 3723 eligible, who underwent interview and detailed dilated ocular eye evaluation by trained professionals were included in this study. Psychometric properties of the HRQOL instrument were evaluated among visually impaired people. Relationships among overall QOL scores and presenting visual acuity in the better eye, specific eye diseases, and demographic variables were examined. RESULTS: Internal consistency was high for the entire questionnaire (alpha = 0.94). Each item of the QOL scale had an adequate item-total correlation (range, 0.25-0.77) greater than 0.2. After adjusting for demographic variables and ocular disease, Subjects with blindness had significantly lower QOL scores. Subjects with glaucoma or corneal disease independent of visual acuity had lower scores than subjects without those eye diseases. Subjects with cataract or retinal disease had significantly lower scores than those without cataract or retinal disease in the model without visual acuity but not when visual acuity was added to the model. CONCLUSIONS: Decreased QOL was associated with the presence of glaucoma or corneal disease independent of visual acuity and with cataract or retinal disease as a function of visual acuity. Visual impairment from uncorrected refractive errors was not associated with decreased QOL.     

Visual impairment in a Taiwanese population: Prevalence,causes, and socioeconomic factors

PURPOSE We sought to estimate the prevalence of visual impairment among an elderly population in urban Taiwan, determine the causes of visual impairment, and gain information about certain socioeconomic factors associated with visual impairment.

METHODS A population-based survey of ocular diseases in residents aged 50 years or older was conducted in Peitou Precinct, Taipei, Taiwan. All participants underwent a comprehensive ophthalmic examination, including visual acuity measurement, using standardized protocols. Demographic data, marital status, employment status, and educational level were gathered through an interview.

RESULTS A total of 2034 participants completed the visual acuity measurements. The prevalence of visual impairment (defined as best-corrected visual acuity in the better eye <6/18) among this population was 2.75% (95% confidence intervals: 2.04%–3.46%). Three major causes of visual impairment were cataract (30.4%), high myopic macular degeneration (25.0%), and age-related macular degeneration (14.3%). In multivariate analysis, age was positively correlated with visual impairment (P < 0.001), and higher education level was associated with a significant decrease in the odds of being visually impaired (P < 0.001). No relation was found between visual impairment and sex, or marital and employment status.

CONCLUSIONS This study provides the first information about the prevalence and causes of visual impairment in Taiwan, and identifies age and educational level as the most important factors related to visual impairment. Additional educational programs should be developed to improve individual awareness of age-related ocular diseases and the availability of current ophthalmic intervention.     

Prevalence of visual impairment, blindness, and cataract surgery in the Hong Kong elderly

BACKGROUND: The prevalence of vision impairment, unilateral/bilateral blindness, and cataract surgery were estimated in a population based survey among the elderly in a suburban area of Hong Kong. METHODS: 15 public, private, and home ownership scheme housing estates in the Shatin area of Hong Kong were subjected to cluster sampling to randomly select a cross section of people 60 years of age or older. Visual acuity measurements and ocular examinations were conducted at a community site within each estate. The principal cause of reduced vision was identified for eyes with presenting visual acuity worse than 6/18. RESULTS: A total of 3441 subjects from an enumerated population of 4487 (76.7%) completed an eye examination. The prevalence of presenting visual acuity less than 6/18 in at least one eye was 41.3%; and 73.1% in those 80 years of age or older. Unilateral blindness (acuity <6/60) was found in 7.9% of subjects and bilateral blindness in 1.8%. Refractive error and cataract were, respectively, the main causes of vision impairment and blindness. Visual impairment with either eye <6/18 increased with advancing age and was more prevalent in males, the less educated, and those living in public housing estates. The prevalence of cataract surgery was 9.1% and was associated with advancing age and less education. CONCLUSIONS: Blindness and visual disability were common in this socioeconomically advanced population, with most of it easily remedied. Because of a rapidly ageing population, healthcare planners in Hong Kong must prepare for an increasing burden of visual disability and blindness.     

Relationship between vision impairment and eye disease to vision-specific quality of life and function in rural India: the Aravind Comprehensive Eye Survey

PURPOSE: To determine the impact of vision impairment and eye diseases on vision-specific quality of life and visual function in an older population of rural southern India. METHODS: Presenting and best-corrected visual acuity and burden of eye diseases were determined in a population aged 40 years and older, identified through a random cluster sampling strategy from 50 villages of rural south India. A questionnaire validated previously for use in this population was used to ascertain quality of life and visual function. Visual acuity measurements were obtained with illiterate E Early Treatment Diabetic Retinopathy Study (ETDRS) charts. Cataract was graded and defined based on the Lens Opacities Classification System (LOCS) III. Macular degeneration was defined based on the classification system proposed by the International ARM Epidemiologic Study Group. Glaucoma was defined based on results of clinical examinations including optic disc and visual fields. Analyses were performed to explore the relationship of overall and subscale quality-of-life and visual function scores with presenting acuity in the better-seeing eye, specific eye diseases, and demographic variables. RESULTS: Information on quality of life and visual function were available for 5119 (99.4%) of 5150 study subjects. The mean presenting visual acuity in the better eye was 0.76 +/- 0.53 logMAR (logarithm of the minimum angle of resolution) units. Age, education, occupation, presenting acuity in the better eye, and presence of a cataract, glaucoma, or refractive error were independently associated with overall quality-of-life and vision function scores. After adjustment for demographic variables and ocular disease, persons with vision impairment or bilateral blindness based on presenting visual acuity had lower scores across all domains of quality of life and vision function. Scores for subscales of quality-of-life and vision function domains were significantly lower among those with age-related cataract and glaucoma compared with persons without those eye diseases. CONCLUSIONS: Presenting vision in the better eye was associated with quality of life and vision function in this older population of rural south India. Subjects with glaucoma and age-related cataract had an associated decrease in quality of life and vision function, independent of presenting visual acuity in the better eye.     

Assessment of vision-related quality of life in an older population subsample: The Blue Mountains Eye Study

PURPOSE: To assess visual functioning and vision-specific health-related quality of life (HRQOL) in an older, community-dwelling-based population subsample, using the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25). METHODS: Three-quarters (76%, n = 892) of Extension Blue Mountains Eye Study participants (aged > or = 50 years, mean 60.8 years) completed the self-administered NEI-VFQ-25, an instrument consisting of 12 dimensions and one summary composite score, and comprehensive eye examinations, including monocular distance visual acuity. Visual impairment was defined as visual acuity < 6/12. Unilateral and bilateral visual impairment was defined by the worse eye and better eye, respectively. Correctable visual impairment was defined as that which improved, and non-correctable visual impairment as that which persisted after subjective refraction. Mild visual impairment was defined as visual acuity < 6/12 but > or = 6/24, moderate as < 6/24 but > or = 6/60, and severe as < 6/60. RESULTS: There were no significant differences in age, sex, or vision status between NEI-VFQ-25 responders and non-responders. Men had significantly better scores in three subscales than women but there were no significant differences in their overall composite scores (men 88.5+/- 0.5; women 88.1+/- 0.4). Persons aged 60-69 years had the best NEI-VFQ-25 profiles (mean composite score +/- standard error, 90.2 +/- 0.5; 50-59 years, 88.5 +/- 0.4; > or =70 years, 86.2 +/- 0.8). Presenting bilateral visual impairment (77.1 +/- 1.4) was associated with significantly poorer functioning than unilateral (87.5 +/- 0.8) or no visual impairment (89.4 +/- 0.3). Increasing levels of impairment were associated with poorer levels of visual functioning. The impact of impairment was principally from non-correctable (49.2 +/- 2.6) rather than refractive impairments (85.3 +/- 1.4), although the latter accounted for over three-quarters (77.5%) of presenting bilateral impairment. Non-correctable unilateral impairment (85.3 +/- 1.1) was associated with poorer functioning than no impairment. CONCLUSIONS: The findings from this community-dwelling older population show that the NEI-VFQ-25 differentiates well between various levels of visual impairment with regard to the magnitude of their impact on vision-specific quality of life. Greater impacts were noted among persons with bilateral compared to unilateral impairment, with increasing impacts at greater severities of visual impairment. Visual impairment from refractive errors is more frequent than from underlying pathologic disorders, but the impact of correctable visual impairment was considerably milder than the impact of non-correctable visual impairment.     

Visual acuity in northern China in an urban and rural population: the Beijing Eye Study

AIM: To evaluate prevalence and demographic associations of visual impairment in an urban and rural population in northern China. METHODS: In the Beijing Eye Study, a population based cohort study in northern China, visual acuity was assessed for 8876 eyes (4438 subjects) according to a response rate of 83.4%. The study was divided into a rural part (1972 subjects) and an urban part (n=2466). Mean age was 56.20 (SD 10.59) years (median 56 years; range 40-101 years). RESULTS: Mean uncorrected visual acuity measured 0.72 (0.32) (median, 0.80), and mean best corrected visual acuity measured 0.91 (0.21) (median, 1.0). In a multiple regression analysis, best corrected visual acuity was significantly correlated with age (p<0.001), degree of nuclear cataract (p<0.001), amount of cortical cataract (p=0.014), amount of subcapsular cataract (p<0.001), educational background (p<0.001), and refractive error (p<0.001). Rural region versus urban region (p=0.34) and sex (p=0.053) were not statistically significantly associated with best corrected visual acuity. CONCLUSIONS: In northern China, determinants of a low degree of best corrected visual acuity are age, cataract, low educational background, and myopia. Despite marked differences in educational background and family income, sex, and rural area versus urban area are not markedly associated with best corrected visual acuity.