The methodology of visual field testing with frequency doubling technology in the National Health and Nutrition Examination Survey, 2005-2006.
ABSTRACT To describe the frequency doubling technology (FDT) methodology to measure visual field loss in the National Health and Nutrition Examination Survey and to evaluate data reliability.
Participants aged 40 years and older were eligible (n = 2,529) for 2 visual field tests per eye performed with the Humphrey Matrix N-30-5 screening test. Visual field loss was determined using a 2-2-1 algorithm requiring 2 complete tests per eye, with at least 2 abnormal field results in each test, and 1 common abnormal field.
Response rate was 86.2%. Time constraints were the main reason for no exam (55.6%). Median times were: single test, 37 seconds; entire exam, 9.1 minutes. When defining reliability based on ≤ 1/3 blind spots, ≤ 1/3 false positive tests, and technician noted proper fixation, 80.1% of examined adults had 2 reliable tests for both eyes; an additional 13.4% had 2 reliable tests for 1 eye. Increasing age, decreasing visual acuity, and the presence of self-reported glaucoma resulted in decreased examination rates, increased test times, and decreased data reliability. Sensitivity and specificity to detect persons with glaucoma was 54.8% and 91.9%, respectively.
FDT is a feasible, fast, and reliable method for visual field loss screening in a population-based U.S. study, with an 86.2% response rate, median exam time ~9 minutes, and nearly 95% of examined participants having complete, reliable results in 1 or both eyes.
SourceAvailable from: Denise A Valenti[Show abstract] [Hide abstract]
ABSTRACT: This study was to investigate the feasibility of frequency doubling technology (FDT) visual field testing in Alzheimer's disease (AD) in order to identify early biomarkers of AD in patients already diagnosed with AD and compare the findings to participants not having Alzheimer's disease. This biomarker would be useful in a battery of tests for the early identification of those with AD. It was not the intent to correlate the visual system biomarker with severity of disease, but to determine if the biomarker was present in pass or fail screening criteria. The study showed with very strong significance that the FDT can identify biomarkers of those with AD compared to an age-matched population that does not have AD. FDT is a simple test to take and administer and has been used to screen for eye and retinal diseases such as glaucoma, retinal macular degeneration, and diabetic retinopathy. The results obtained in the FDT readout are analyzed and compared to the age normative database within the system. The FDT ability to screen for AD biomarker in the visual system was significant in those with AD compared to the controls, and the deficits were not related to any ocular pathology.01/2013; 2013:989583. DOI:10.1155/2013/989583
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ABSTRACT: Purpose To assess vision health disparities in the United States by race/ethnicity, education, and economic status. Design Cross-sectional, nationally representative samples. Methods We used national survey data from the National Health and Nutrition Examination Survey (NHANES) and the National Health Interview Survey (NHIS). Main outcome measures included, from NHANES, age-related eye diseases (ie, age-related macular degeneration [AMD], cataract, diabetic retinopathy [DR], glaucoma) and from NHIS, eye care use (ie, eye doctor visits and cannot afford eyeglasses when needed) among those with self-reported visual impairment. The estimates were age- and sex-standardized to the 2000 US Census population. Linear trends in the estimates were assessed by weighted least squares regression. Results Non-Hispanic whites had a higher prevalence of AMD and cataract surgery than non-Hispanic blacks, but a lower prevalence of DR and glaucoma (all P < .001 in NHANES 2005-2008). From 1999 to 2008, individuals with less education (ie, high school) and lower income (poverty income ratio [PIR] <1.00 vs ≥4.00) were consistently less likely to have had an eye care visit in the past 12 months compared with their counterparts (all P < .05). During this period, inability to afford needed eyeglasses increased among non-Hispanic whites and Hispanics (trend P = .004 and P = .007; respectively), those with high school education (trend P = .036), and those with PIR 1.00-1.99 (trend P < .001). Conclusions Observed vision health disparities suggest a need for educational and innovative interventions among socioeconomically disadvantaged groups.American Journal of Ophthalmology 12/2012; 154(6):S53–S62.e1. DOI:10.1016/j.ajo.2011.08.045 · 4.02 Impact Factor
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ABSTRACT: To investigate the association between visual field defects and quality of life in the United States population. Cross-sectional study. A total of 5186 participants in the 2005 through 2008 National Health and Nutrition Examination Survey 40 years of age and older without a self-reported history of age-related macular degeneration or prior refractive surgery who had undergone frequency doubling technology perimetric testing. Frequency doubling technology perimetry was performed in both eyes. Results from the better eye were used to categorize subjects as normal or having mild, moderate, or severe visual field loss. Subjects completed surveys about their visual and physical functioning ability. Disability pertaining to 6 vision-related activities, 2 visual function questions, and 5 physical functioning domains. Eighty-one percent of subjects had normal visual fields and 10%, 7%, and 2% demonstrated mild, moderate, and severe visual field defects, respectively. Subjects with greater severity of visual field defects had greater difficulty with vision-related activities. Subjects with severe visual field defects demonstrated the greatest odds of difficulty with all 6 activities. The 2 activities impacted most adversely were daytime driving in familiar places (odds ratio [OR], 12.4; 95% confidence interval [CI], 6.1-25.1) and noticing objects off to the side when walking (OR, 7.7; 95% CI, 4.7-12.7). Subjects with severe visual field defects had greater odds of worrying about eyesight (OR, 3.4; 95% CI, 2.0-5.8) and being limited by vision in the time spent on daily activities (OR, 5.1; 95% CI, 3.0-8.5). Subjects with severe visual field defects demonstrated the greatest odds of difficulty with 3 physical function domains, including activities of daily living (OR, 2.45; 95% CI, 1.37-4.38), instrumental activities of daily living (OR, 2.45; 95% CI, 1.37-4.38), as well as leisure and social activities (OR, 3.29; 95% CI, 1.87-5.77). Greater severity of visual field abnormality was associated with significantly greater odds of disability with vision-related function and physical function. These findings support the necessity of routine screening to find those who may benefit from therapy to prevent progressive glaucomatous vision loss. The author(s) have no proprietary or commercial interest in any materials discussed in this article.Ophthalmology 12/2013; DOI:10.1016/j.ophtha.2013.09.043 · 6.17 Impact Factor