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C A McCarty

Publications and source records attributed to C A McCarty.

At least 73 records · Page 4Linked to original sources

Adaptation of WHOQOL as health-related quality of life instrument to develop a vision-specific instrument.

The WHOQOL instrument was adapted as a health-related QOL instrument for a population-based epidemiologic study of eye diseases in southern India, the Andhra Pradesh Eye Disease Study (APEDS). A follow-up question was added to each item in WHOQOL to determine whether the decrease in QOL was due to any health reasons including eye-related reasons. Modifications in WHOQOL and translation in local language were done through the use of the focus groups including health professionals and people not related to health care. The modified instrument has 28 items across 6 domains of the WHOQOL and was translated into the local language, Telugu, using the pragmatic approach. It takes 10-20 minutes to be administered by a trained interviewer. Reliability was within acceptable range. This health-related QOL instrument is being used in the population-based study APEDS to develop a vision-specific QOL instrument which could potentially be used to assess the impact of visual impairment on QOL across different cultures and for use in evaluating eye-care interventions. This health-related QOL instrument could also be used to develop other disease-specific instruments as it allows assessment of the extent to which various aspects of QOL are affected by a variety of health problems.

Adult↗

Prevalence and risk factors of myopia in Victoria, Australia.

OBJECTIVE: To determine the prevalence and risk factors of myopia in urban and rural Victoria, Australia. PARTICIPANTS AND METHODS: The Visual Impairment Project is a population-based prevalence study of eye disease in which both urban and rural adult populations were examined. Refractive data on the participants were collected using logMAR visual acuity, corrective lens measurement, and subjective refraction. All refractive error data were converted into spherical equivalent and myopia was defined at 2 levels: worse than -0.5 diopters (D) and worse than -1.00 D. RESULTS: A total of 3271 (83%) urban and 1473 (91%) rural residents were examined. The overall prevalence of myopia worse than -0.50 D in the population was 17% (95% confidence limit = 15.8%, 18.0%). Prevalence of myopia decreased from 24% in those aged 40 to 49 years to 12% in those aged 70 to 79 years, and then increased to 17% in people older than 80 years. The younger age groups also had higher usage of myopic corrective lenses throughout their lives than the older age groups, indicating an increased use of myopic corrective lenses in recent times. Myopia was found to be significantly higher in people with higher education levels (chi2 = 119.20, P < .001), in clerks and professionals (chi2 = 132.53, P < .001), in people born in southeast Asia (chi2 = 77.62, P < .001), and in people with higher degrees of nuclear opacity (chi2 = 55.26, P < .001). CONCLUSION: Myopia rates in the Visual Impairment Project generally decrease with age and use of myopic correction has increased in recent times. Myopia was significantly related to education level, occupation, country of birth, and nuclear opacity.

Adult↗

Prevalence and predictors of undercorrected refractive errors in the Victorian population.

PURPOSE: To investigate the prevalence and predictors of undercorrected refractive errors in the Victorian population. METHODS: In this prospective study, a population-based sample of residents was recruited. The improvement in visual acuity with subjective refraction was assessed. Several individual characteristics were investigated as predictors of undercorrected refractive error. RESULTS: There were 5,615 eligible residents, of which 4,735 (84%) participated in the study (53% were women). In all, 466 participants (10%) had significant undercorrected refractive error leading to an improvement of 1 or more lines of visual acuity with refraction. Age was the most important predisposing factor. The risk of undercorrected refractive error increased by 1.8 times for every decade of life starting at 40 years of age. The next most important factor was the absence of distance refractive correction. These individuals were 6.8 times more at risk compared with those who wore distance spectacles. Other significant predictors of undercorrected refractive error were the presence of cataract and European or Middle Eastern languages spoken at home. People with tertiary education or hypermetropia were less likely to need refractive error improvement. Gender, country of birth, and employment status did not have any statistically significant effect after controlling for confounders. CONCLUSIONS: The results of this study disclose people in the community who are more at risk of compromising their vision because of undercorrected refractive errors. A campaign is warranted to alert people that it may be possible to improve their vision.

Adult↗

Population-based assessment of the outcome of cataract surgery in an urban population in southern India.

PURPOSE: To assess the outcome of cataract surgery in an urban population in southern India. METHODS: As part of a population-based cross-sectional epidemiologic study, the Andhra Pradesh Eye Disease Study, 2,522 people of all ages, including 1,399 individuals 30 years of age or older, from 24 clusters representative of the population of Hyderabad in southern India underwent a detailed interview and ocular evaluation including logarithm of minimal angle of resolution (logMAR) visual acuity, refraction, slit-lamp biomicroscopy, applanation tonometry, gonioscopy, dilation, cataract grading, aphakia/pseudophakia status, and stereoscopic fundus evaluation. Automated threshold visual fields and slit-lamp and fundus photography were performed when indicated by standardized criteria. Very poor outcome in an eye that had undergone cataract surgery was defined as presenting distance visual acuity worse than 20/200, and poor outcome was defined as visual acuity worse than 20/60 to 20/200. RESULTS: In subjects 50 years of age or older, after adjustment for age and sex distribution, the rate of having had cataract surgery in one or both eyes was 14.6% (95% confidence interval [CI], 11.4% to 17.8%). Of 131 eyes (91 subjects) that had undergone cataract surgery, 28 (21.4%; 95% CI, 14.4% to 28.4%) had very poor outcome and another 40 (30.5%; 95% CI, 22.6% to 38.4%) had poor outcome. The very poor outcome in 20 (71.4%) of 28 eyes and poor outcome in 23 (57.5%) of 40 eyes could be attributed to surgery-related causes or inadequate refractive correction. With multivariate analysis, very poor outcome as a result of surgery-related causes or inadequate refractive correction was more likely to be associated with intracapsular cataract extraction than with extracapsular cataract extraction (odds ratio, 9.34; 95% CI, 2.49 to 35.06) in subjects belonging to the lowest socioeconomic status (odds ratio, 4.92; 95% CI, 1.16 to 20.93) and with date of surgery 3 or fewer years before the survey than with more than 3 years (odds ratio, 4.52; 95% CI, 1.33 to 15.39). Also, very poor or poor outcome as a result of surgery-related causes or inadequate refractive correction was associated with women (odds ratio, 2.55; 95% CI, 1.06 to 6.16). CONCLUSIONS: The very high rate of very poor and poor visual outcome, predominantly as a result of surgery-related causes and inadequate refractive correction, in this urban population of India suggests that more attention is needed to improve the visual outcome of cataract surgery. In order to deal with cataract-related visual impairment in India, as much emphasis on surgical quality, refractive correction, and follow-up care is necessary as on the number of surgeries.

Adult↗

The epidemiology of cataract in Australia.

PURPOSE: To describe the prevalence and risk factors for cataract in an Australian population aged 40 years and older. METHODS: Participants were recruited by a household census and stratified, random cluster sampling to represent residents of Victoria, Australia, aged 40 years and older. The following information was collected: initial visual acuity and best-corrected visual acuity, demographic details, health history, dietary intake of antioxidants, lifetime ocular ultraviolet B exposure, and clinical eye examination, including lens photography. Cortical opacities were measured in sixteenths. Cortical cataract was defined as opacity greater than or equal to 4/16 of pupil circumference. Nuclear opacities were graded according to the Wilmer cataract grading scheme, and cataract was defined as greater than or equal to nuclear standard 2.0 of four standards. The height and width of any posterior subcapsular opacity was measured and recorded. Posterior subcapsular cataract was defined as posterior subcapsular opacity greater than or equal to 1 mm2. The worse eye was selected for analysis. Backward stepwise logistic regression was used to quantify independent risk factors for cataract. RESULTS: A total of 3,271 (83% of eligible) of the urban residents, 403 (90% of eligible) nursing home residents, and 1,473 (92% of eligible) rural residents participated. The urban residents ranged in age from 40 to 98 years (mean, 59 years), and 1,511 (46%) were men. The nursing home residents ranged in age from 46 to 101 years (mean, 82 years), and 85 (21%) were men. The rural residents ranged in age from 40 to 103 years (mean, 60 years), and 701 (47.5%) were men. The overall weighted rate of cortical cataract was 11.3% (95% confidence limits, 9.68%, 13.0%) excluding cataract surgery and 12.1% (95% confidence limits, 10.5%, 13.8%) including cataract surgery. The risk factors for cortical cataract that remained in the multivariate logistic regression model were age, female gender, diabetes duration greater than 5 years, gout duration greater than 10 years, arthritis diagnosis, myopia, use of oral beta-blockers, and increased average annual ocular ultraviolet B exposure. Overall, 12.6% (95% confidence limits, 9.61%, 15.7%) of Victorians aged 40 years and older had nuclear cataract including previous cataract surgery, and 11.6% (95% confidence limits, 8.61%, 14.7%) had nuclear cataract excluding previous cataract surgery. In the urban and rural cohorts, age, female gender, rural residence, brown irides, diabetes diagnosed 5 or more years earlier, myopia, age-related maculopathy, having smoked for greater than 30 years, and an interaction between ocular ultraviolet B exposure and vitamin E were all risk factors for nuclear cataract. The rate of posterior subcapsular cataract excluding previous cataract surgery was 4.08% (95% confidence limits, 3.01%, 5.14%), whereas the overall rate of posterior subcapsular cataract including previous cataract surgery was 4.93% (95% confidence limits, 3.68%, 6.17%) . The independent risk factors for posterior subcapsular cataract in the urban and rural cohorts that remained were age in years, rural location, use of thiazide diuretics, vitamin E intake, and myopia. CONCLUSIONS: The expected increase in the prevalence of cataract with the aging of the population highlights the need to plan appropriate medical services and public health interventions for primary and secondary prevention. Many of the identified risk factors for cataract in the population have the potential for being modified through public health interventions.

Adult↗

Burden of moderate visual impairment in an urban population in southern India.

OBJECTIVE: To assess the prevalence and causes of moderate visual impairment in an urban population in southern India. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: A total of 2522 (85.4% of the eligible) persons of all ages, including 1399 persons 30 years of age or older, from 24 clusters representative of the population of Hyderabad city. TESTING: The eligible subjects underwent a detailed ocular evaluation, including logarithm of the minimum angle of resolution (logMAR) visual acuity, refraction, slit-lamp biomicroscopy, applanation tonometry, gonioscopy, cataract grading, and stereoscopic dilated fundus evaluation. Automated threshold visual fields and slit-lamp and fundus photography were done when indicated by standardized criteria. MAIN OUTCOME MEASURE: Moderate visual impairment was defined as presenting distance visual acuity less than 20/40 to 20/200 or visual field loss by predefined standardized conservative criteria in the better eye. RESULTS: In addition to the 1% prevalence of blindness in this sample reported earlier, moderate visual impairment was present in 303 subjects, an age-gender-adjusted prevalence of 7.2% (95% confidence interval [CI], 4.5%-9.9%; design effect, 2.7). The major cause of moderate visual impairment was refractive error (59.4%, 95% CI, 52.3%-66.5%) followed by cataract (25.3%, 95% CI, 19%-31.6%). Multivariate analysis showed that the prevalence of moderate visual impairment was significantly higher in those 40 years of age or older (odds ratio, 10.9; 95% CI, 8-15) and females (odds ratio, 1.89; 95% CI, 1.41-2.53) and lower in those belonging to the highest socioeconomic status (odds ratio, 0.27; 95% CI, 0.14-0.51). However, because of the pyramidal age distribution of the population, 38.1% of the total moderate visual impairment was present in those younger than 40 years of age. The proportion of moderate visual impairment caused by refractive error was higher in the younger than in the older age groups (P < 0.0001). CONCLUSIONS: Projecting the results to the 26.5% urban population of India, there would be 18.4 million (95% CI, 11.5-25.2 million) persons with moderate visual impairment in urban India alone. Refractive error was the major cause of moderate visual impairment in the population studied. The absolute proportion of moderate visual impairment in those younger than 40 years of age was considerable. The eyecare policy of India, apart from dealing with blindness, should address the issue of the relatively easily treatable uncorrected refractive error as the cause of moderate visual impairment in an estimated 10.9 million persons in urban India.

Adolescent↗

Schizophrenia, psychotropic medication, and cataract.

OBJECTIVE: To compare the distribution of cataract types between psychiatric patients diagnosed with schizophrenia and the general population not exposed to psychotropic medication, and to compare cataract prevalence between users and nonusers of various psychotropic medications in the general community. DESIGN: Case-control. PARTICIPANTS: A total of 151 (93%) eligible patients from a community mental health service and 3271 (83%) eligible residents from the Melbourne Visual Impairment Project (VIP) were examined. MAIN OUTCOME MEASURES: All patients 40 years of age and older from a community mental health service and residents of nine randomly selected areas of Melbourne were eligible. Best-corrected distance visual acuity was determined using a 4-m logarithm of the minimum angle of resolution (LogMAR) chart. The presence of cataract was determined by photographs or slit-lamp examination using direct and indirect retroillumination. Anterior, cortical, nuclear, and posterior subcapsular cataracts were measured. Participants from the Melbourne VIP were classified as to whether they had taken benzodiazepams, phenothiazines, thioxanthenes, butyrophenols, tricyclic antidepressants, or monoamine oxidase inhibitors for at least 12 months during their lifetime. RESULTS: The distribution of cataract type varied between persons with and without schizophrenia. Anterior subcapsular (ASC) cataract was significantly more prevalent (26%) in participants with schizophrenia from the community mental health service than Melbourne VIP participants (0.2%) not exposed to psychotropic medication (chi-square, 1 degree of freedom = 605.5, P = 0.001). This remained significant after controlling for age (odds ratios = 250, 95% confidence interval = 83.3, 1000). The distribution of the age-related cataract was similar across all groups of psychotropic medication users with the exception of the phenothiazine users. They had less of all types of the age-related cataracts, despite being slightly older than the control group (mean age, 60.0 vs. 58.4, t test = 0.85, P = 0.40). However, only cortical cataract in the phenothiazine group was statistically lower (chi-square, 1 degree of freedom = 3.96, P = 0.047). CONCLUSION: This study has identified the need to investigate whether other newer agents, especially high-potency medications, cause ASC opacities if a certain threshold of exposure to psychotropic medications must be attained to develop cataract, or if schizophrenia itself is associated with cataract formation.

Adult↗

Epidemiology of ocular trauma in Australia.

PURPOSE: To describe the prevalence and risk factors of ocular trauma in a representative sample of Australians aged 40 and over who reside in the state of Victoria. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Australians aged 40 years and older living in Victoria. METHODS: Cluster, stratified sampling was used to identify permanent residents for a population-based study of eye disease. A standardized examination that included visual acuity and information about ocular trauma was conducted. MAIN OUTCOME MEASURES: Self-reported history of ocular trauma and circumstances surrounding the events. RESULTS: A total of 3271 (83% of eligible) Melbourne residents and 1473 (92% of eligible) rural residents were examined. The overall rate of eye injury history in Victoria was 21.1% (95% confidence limits [CL] 19.6%, 22.5%). Men were far more likely than women to have ever experienced an eye injury (34.2% versus 9.9%), and rural men were more likely than Melbourne men to have ever had an eye injury (42.1 % versus 30.5%). The workplace accounted for the majority of eye injuries (60%), followed by the home (24%). The location with the highest percent of people reporting the use of eye protection at the time of the injury was the workplace (18.5%); the workplace accounted for the lowest rate of hospitalization (4.9%). The industry with highest cumulative rate of eye injuries was communication (14 per 1000), whereas the highest occupation-specific cumulative rates of eye injury were recorded for tradespersons (18 per 1000). CONCLUSIONS: Although ocular trauma is usually not associated with bilateral vision impairment, it is a major public health problem in Australia. Rural men, people engaged in hammering or sport, and those in the trades are at highest risk and require specific, targeted, prevention messages.

Accidents, Occupational↗

Can we trust parent reports in research on cultural and ethnic differences in child psychopathology? Using the bicultural family design to test parental culture effects.

Research comparing cultural and ethnic groups on child psychopathology has relied heavily on parent reports. But don't parents' own cultural backgrounds bias their reports, undermining valid assessment of actual child behavior? The question is hard to address because parent and child culture tend to be confounded. To solve this problem, we assembled an unusual but heuristically valuable sample: 50 bicultural families, each with an ethnic Thai parent reared in Thailand and a Caucasian parent reared in the U.S. Parents in each pair independently completed standardized problem checklists on the same child in their family. Across all 10 empirically derived problem syndromes, no parental culture effect was either significant or larger than "small," by Cohen's (1988) standards; across all 140 specific problems, the mean percent of variance accounted for by parent culture was less than 1%. Results do not point to a biasing effect of parental culture.

Child↗

Baseline ophthalmic findings in the vitamin E, cataract and age-related maculopathy (VECAT) study.

PURPOSE: To describe the methodology of eye examination and the baseline eye characteristics of the Vitamin E, Cataract and Age-Related Maculopathy (VECAT) study participants. METHODS: A sample of volunteers from an urban area of Melbourne, Australia, were recruited to participate in a randomized, controlled trial investigating the effect of vitamin E on the development of cataract and age-related maculopathy Standardized eye examinations involved clinical assessment, which included Wilmer grading of the lens, digital photography of the lens with Nidek EAS-1000 lens camera and stereo photography of the macular area with the Nidek 3-DX fundus camera. All cases of ophthalmic findings were determined on the basis of pathology in the worse eye. RESULTS: Most eyes were free from abnormalities. The most frequent findings were cataract and age-related macular changes. Nuclear cataract (nuclear opacity grade >2) was present in 4.5%, cortical cataract (cortical opacity grade >2) in 14.3% and posterior subcapsular cataract in 3.0% of participants; in addition, coronary cataract was observed in 13.6%. Soft drusen larger than 125 pm were found in 11.4%, retinal pigment epithelium changes in 9.5%, epiretinal membrane in 6.6% and age-related macular degeneration in 0.5% of participants. SUMMARY: Due to the selection criteria, the majority of participants had clear or minor lens changes and/or minor retinal age-related changes. Precise instrumental documentation will allow an accurate assessment of the incidence and dynamics of these changes throughout 4 years of observation.

Aged↗

Management of diabetic retinopathy by Australian optometrists. Working Group on Evaluation of NHMRC Retinopathy Guideline Distribution. National Health and Medical Research Council.

PURPOSE: To describe current practices related to the management of diabetic retinopathy by Australian optometrists. SETTING AND METHODS: A two-page self-administered questionnaire was mailed to a random sample of 504 Australian optometrists. The survey included questions about the practice (such as size and location); current practice with regard to management of patients with diabetic retinopathy; barriers to use of dilating drops; and a number of patient scenarios related to screening, follow-up and treatment of diabetic retinopathy. RESULTS: Completed questionnaires were returned by 407 of the 473 eligible optometrists (86%). They had been practising optometry between 1 and 50 years (median 14). Of the 243 optometrists who provided details about the location of their practices, 145 (37%) had at least one of their practices in a rural area. The estimated percentage of patients with diagnosed diabetes ranged from 0.5 to 40% (median = 5.0%). Three-hundred and twenty-two optometrists (79%) reported that they would often or almost always ask new patients over the age of 40 whether they have diabetes. The majority of optometrists (n = 387, 95%) would often or almost always ask their new patients with diabetes about their control of blood glucose levels and the majority of optometrists (n = 330, 81%) would often or almost always tell their patients with diabetes about the importance of strict glucose control in delaying retinopathy. The most common barrier to dilated ophthalmoscopy was patients not wanting to be dilated, with 38.1% of optometrists reporting this to be a moderate or major barrier. The next most common barrier was fear of precipitating angle closure glaucoma; 17.1% of optometrists reported this to be a moderate or major barrier CONCLUSION: The National Health and Medical Research Council (NHMRC) guidelines for the management of diabetic retinopathy are timely in relation to the expressed desire of Australian optometrists to learn more about management of diabetic retinopathy These data will be used prospectively to assess changes in management of patients with diabetic retinopathy as a result of the release of the NHMRC guidelines.

Australia↗

The role of past intake of vitamin E in early cataract changes.

PURPOSE: We examined the association between prior supplementation of vitamin E and early cataract changes in volunteers currently enrolled in the cross-sectional VECAT study. The Vitamin E and Cataract Prevention Study (VECAT) is a clinical trial currently in progress, designed to assess the affect of vitamin E supplementation on the development and progression of cataract and age-related macular degeneration. METHODS: A history of vitamin E supplementation was ascertained through a self-administered questionnaire that was mailed to each of the 1,111 participants who were enrolled at the time in the prospective VECAT Study. RESULTS: With a 99% response rate, we found that 26% of participants reported prior supplementation of vitamin E. Only 8.8% of these participants took supplementation greater than the recommended daily intake (RDI) of 10 mg/day. Of these 26%, 57% took supplementation in the form of multivitamins as opposed to a vitamin E supplement on its own. The range of supplement intake ranged from as little as 0.1 mg/day to a maximum of 55 mg/day. A statistically significant association was found between prior supplementation and the absence of cortical opacity (OR = 0.47, 95%CI = 0.28-0.83), after adjusting for age. The levels of nuclear opacity (NO) were not statistically different between those who reported intake and those with no prior vitamin E supplementation. CONCLUSION: Prior vitamin E supplementation may protect VECAT participants from developing at least early cortical cataracts. No apparent protective role in terms of nuclear opacities and nuclear color was found regardless of the level, regularity or duration of intake.

Aged↗

The VECAT study: methodology and statistical power for measurement of age-related macular features. Vitamin E, Cataract, and Age-related Maculopathy Study.

PURPOSES: (1) To develop the methodology for the grading of macular one-frame stereoslides and to assess the reliability of the system. (2) To determine the prevalence of soft drusen (> 63 microm) and pigment abnormalities synonymous with age-related maculopathy (ARM) at baseline, in a clinical trial of volunteers aged between 55 and 80 years of age. (3) To ascertain the power of the study to detect the 4-year incidence and progression of ARM in vitamin E versus placebo treated participants, given the baseline prevalence. METHODS: The 1204 participants enrolled in the Vitamin E, Cataract, and Age-related Maculopathy Study (VECAT) had colour stereoslides of their fundus taken using the Nidek 3-DX mydriatic fundus camera. The stereoslides were graded by two masked graders according to the "International Classification System for ARM and AMD". Assessment of inter- and intra-observer reliability was carried out on a regular basis on 15% of randomly selected slides. Anticipated rates of incidence and progression were based on results reported by the Beaver Dam Eye Study and the Chesapeake Bay Waterman Study. Power estimations were determined using the "nQuery Advisor" software program. Analyses were carried out on the worse affected eye. RESULTS: Inter-observer reliability was moderate to substantial (Kappa 0.5-0.88) whilst intra-observer agreement was high (0.6-1.0). The prevalence of any soft drusen was 32%. Significant associations were found between soft large indistinct drusen, hypopigmentation, hyperpigmentation and age (p = 0.0001, 0.024 and 0.0001, respectively). The study has at least 87% power to detect an odds ratio equal to two for the progression of soft distinct, soft indistinct, hyperpigmentation and hypopigmentation. CONCLUSIONS: The VECAT study methodology appears to be highly reliable and to have sufficient power to detect the differences in the four-year progression of soft distinct and indistinct drusen and pigment abnormalities between the treatment groups.

Aged↗

Methodology of the VECAT study: vitamin E intervention in cataract and age-related maculopathy.

Cataract is the leading cause of blindness in the world today, while age-related macular degeneration is responsible for the majority of new cases of visual impairment in the Western world. There is a growing body of evidence suggesting a role for antioxidant therapy to prevent the progression of these conditions. A 4-year prospective, randomised, controlled trial of an antioxidant versus placebo in a population of healthy volunteers aged 55-80 years at enrolment is described. This paper outlines the primary aims of the Vitamin E, Cataract and Age-related Macular Degeneration (VECAT) Study, the methodology, and the recruitment rates. Additional data on the toxicity and non-ocular effects of vitamin E will also be collected. Standardised clinical grading of macular and lens features, and comparison of serial macular photographs and digital lens photographs will form the basis for assessment of primary study outcomes. Information collected in this study will assist in the assessment of the potential value of antioxidants in preventing the enormous burden imposed on developed communities by age-related eye disease. In addition, important data on prevalence and progression rates of cataract and macular degeneration will be collected.

Aged↗

The need for cataract surgery: projections based on lens opacity, visual acuity, and personal concern.

AIM: To assess the projected needs for cataract surgery by lens opacity, visual acuity, and patient concern. METHODS: Data were collected as part of the Melbourne Visual Impairment Project, a population based study of age related eye disease in a representative sample of Melbourne residents aged 40 and over. Participants were recruited by a household census and invited to attend a local screening centre. At the study sites, the following data were collected: presenting and best corrected visual acuity, visual fields, intraocular pressure, satisfaction with current vision, personal health history and habits, and a standardised eye examination and photography of the lens and fundus. Lens photographs were graded twice and adjudicated to document lens opacities. Cataract was defined as nuclear greater than or equal to standard 2, 4/16 or greater cortical opacity, or any posterior subcapsular opacities. RESULTS: 3271 (83% response) people living in their own homes were examined. The participants ranged in age from 40 to 98 years and 1511 (46.2%) were men. Previous cataract surgery had been performed in 107 (3.4%) of the participants. The overall prevalence of any type of cataract that had not been surgically corrected was 18%. If the presence of cataract as defined was considered the sole criterion for cataract surgery with no reference to visual acuity, there would be 309 cataract operations per 1000 people aged 40 and over (96 eyes of people who were not satisfied with their vision, 210 eyes of people who were satisfied with their vision, and three previous cataract operations). At a visual acuity criterion of less than 6/12 (the vision required to legally drive a car), 48 cataract operations per 1000 would occur and people would be twice as likely to report dissatisfaction with their vision. CONCLUSIONS: Estimates of the need for cataract surgery vary dramatically by level of lens opacity, visual acuity, and patient concern. These data should be useful for the planning of health services.

Adult↗

Population based assessment of diabetic retinopathy in an urban population in southern India.

AIM: To assess the prevalence of diabetic retinopathy and the visual impairment caused by it in an urban population in southern India in order to determine its public health significance. METHODS: 2522 subjects (85.4% of those eligible), a representative sample of the population of Hyderabad city in southern India, underwent interview and detailed dilated eye examination during 1996-7 as part of the Andhra Pradesh Eye Disease Study. RESULTS: 124 subjects, all >/=30 years old, reported that they had diabetes, an age-sex adjusted prevalence of 7.82% (95% confidence interval (CI) 5.76-9.88%) in this age group. Diabetes was diagnosed at age >/=30 years in all but two subjects. The duration since diagnosis of diabetes was <10 years in 75.6% and >/=15 years in 6.7%. Diabetic retinopathy was present in 28 subjects, 1.78% (95% CI 1.09-2.48%) of those >/=30 years old. Most of the diabetic retinopathy was of the mild (50%) or moderate (39.3%) non-proliferative type; one subject (3.6%) had proliferative retinopathy. Multiple logistic regression revealed that the odds of having diabetic retinopathy were significantly higher in those >/=50 years than in those 30-49 years old (odds ratio 7.78, 95% CI 2.92-20. 73). Three subjects had visual impairment between 6/12 and 6/38 in either eye due to diabetic retinopathy, 0.19% (95% CI 0-0.41%) of those >/=30 years old. CONCLUSION: Visual impairment due to diabetic retinopathy was relatively uncommon in this urban Indian population in 1996-7. However, this could change in the near future with an increase in duration of diabetes because of the anticipated aging of India's population and the recent suggestion of increase in diabetes prevalence in urban India, and therefore should be monitored.

Adult↗

Variability in digital assessment of cortical and posterior subcapsular cataract.

To identify validity of the standardised Nidek EAS-1000 retroillumination image analysis, images of 450 consecutive patients were analysed for the standard 6.5 mm and for the maximal pupil size. The software allows for separation of cortical and posterior subcapsular opacities and defines threshold for cataract automatically at 12% below the brightest point of the histogram of pixel luminescence. The results were compared with clinical Wilmer cataract grading. Correlation between clinical and digital assessment was 0.48* for cortical opacities in maximal pupil size, 0. 47* in 6.5 mm pupil size analyses, and 0.71* for posterior subcapsular opacities (*p < 0.001). In 24.6% of maximal pupil size analyses and in 11.7% of standard pupil size analyses standardisation revealed confounding features, such as other opacities of media, refractive shadows etc., that masqueraded as cataract and interfered with the cortical opacity measurements. Automatic standardized analysis has reduced many sources of observer variation (level of illumination, pupil size and threshold adjustment), but the revealed range of confounding opacities and artifacts still requires observer interpretation.

Aged↗