Chelsea L Reighard1, Manju R Pillai2, Sujani Shroff2, George L Spaeth3, Stephen G Schilling4, Sheryl S Wizov3, Joshua D Stein1,5,6, Alan L Robin1,7,8, Vidya Raja2, Joshua R Ehrlich1,5. 1. Department of Ophthalmology and Visual Sciences, Center for Eye Policy and Innovation, University of Michigan, Ann Arbor, MI, USA. 2. Aravind Eye Hospital, Madurai, Tamil Nadu, India. 3. Wills Eye Hospital, Thomas Jefferson University, Philadelphia, PA, USA. 4. Institute of Social Research, University of Michigan, Ann Arbor, MI, USA. 5. Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor, MI, USA. 6. Department of Health Management and Policy, School of Public Health, University of Michigan, Ann Arbor, MI, USA. 7. Department of Ophthalmology, Johns Hopkins University, Baltimore, MD, USA. 8. Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
Abstract
Objective/Purpose: Performance-based measures may provide an objective assessment of how glaucoma affects daily functioning. We sought to validate a clinically-applicable performance-based measure of visual ability for patients with glaucoma in south India and to describe its relationship to clinical and patient-reported outcomes. Design: Cross-sectional validation study. Subjects/Participants/Controls: 145 participants with glaucoma were recruited at Aravind Eye Hospital. Methods/Intervention/Testing: We modified the compressed assessment of activities related to vision (CAARV), a performance-based measure validated in the U.S., to be culturally relevant in south India. Participants underwent a series of tests, including the Indian CAARV (I-CAARV), Indian Visual Functioning Questionnaire (IND-VFQ), Spaeth/Richman Contrast Sensitivity (SPARCS) test, standard automated perimetry, and visual acuity (VA). Factor analysis and Rasch modeling were used to validate the I-CAARV. Correlations between the I-CAARV and other outcomes were evaluated. Main Outcome Measure: Psychometric properties of the I-CAARV for individuals with glaucoma in south India. Results: The study included 142 participants (51.7% female, mean age 56.4 years). Average presenting visual acuity and visual field mean deviation (MD) in the better-seeing eye were 0.26 logMAR and -6.57 dB, respectively. The four tasks of the I-CAARV were found to measure a single underlying construct. Rasch analysis of the I-CAARV revealed that the outcome measure had moderate reliability, good construct and content validity, and fair measurement precision. Tasks were well-targeted to the study sample. Rasch-calibrated scores on the I-CAARV were significantly correlated with Rasch-calibrated IND-VFQ scores (r=-0.54) and with visual field MD, presenting VA, best-corrected VA, and SPARCS contrast sensitivity in both the better-seeing eye (r=0.60, -0.51, -0.53, 0.76, respectively) and worse-seeing eye (r=0.48, -0.61, -0.46, 0.69, respectively). Conclusions: The I-CAARV is a valid performance-based measure of vision-dependent functioning in glaucoma in south India. This study also found that I-CAARV task performance was strongly correlated with contrast sensitivity and suggests that performance-based and patient-reported outcomes are related but distinct measures of the impact of glaucoma on functioning and vision-related quality of life. Future studies are needed to determine the sensitivity of the I-CAARV to detect changes due to disease progression that are relevant to functioning and vision-related quality of life.
Objective/Purpose: Performance-based measures may provide an objective assessment of how glaucoma affects daily functioning. We sought to validate a clinically-applicable performance-based measure of visual ability for patients with glaucoma in south India and to describe its relationship to clinical and patient-reported outcomes. Design: Cross-sectional validation study. Subjects/Participants/Controls: 145 participants with glaucoma were recruited at Aravind Eye Hospital. Methods/Intervention/Testing: We modified the compressed assessment of activities related to vision (CAARV), a performance-based measure validated in the U.S., to be culturally relevant in south India. Participants underwent a series of tests, including the Indian CAARV (I-CAARV), Indian Visual Functioning Questionnaire (IND-VFQ), Spaeth/Richman Contrast Sensitivity (SPARCS) test, standard automated perimetry, and visual acuity (VA). Factor analysis and Rasch modeling were used to validate the I-CAARV. Correlations between the I-CAARV and other outcomes were evaluated. Main Outcome Measure: Psychometric properties of the I-CAARV for individuals with glaucoma in south India. Results: The study included 142 participants (51.7% female, mean age 56.4 years). Average presenting visual acuity and visual field mean deviation (MD) in the better-seeing eye were 0.26 logMAR and -6.57 dB, respectively. The four tasks of the I-CAARV were found to measure a single underlying construct. Rasch analysis of the I-CAARV revealed that the outcome measure had moderate reliability, good construct and content validity, and fair measurement precision. Tasks were well-targeted to the study sample. Rasch-calibrated scores on the I-CAARV were significantly correlated with Rasch-calibrated IND-VFQ scores (r=-0.54) and with visual field MD, presenting VA, best-corrected VA, and SPARCS contrast sensitivity in both the better-seeing eye (r=0.60, -0.51, -0.53, 0.76, respectively) and worse-seeing eye (r=0.48, -0.61, -0.46, 0.69, respectively). Conclusions: The I-CAARV is a valid performance-based measure of vision-dependent functioning in glaucoma in south India. This study also found that I-CAARV task performance was strongly correlated with contrast sensitivity and suggests that performance-based and patient-reported outcomes are related but distinct measures of the impact of glaucoma on functioning and vision-related quality of life. Future studies are needed to determine the sensitivity of the I-CAARV to detect changes due to disease progression that are relevant to functioning and vision-related quality of life.
Authors: S K Gupta; K Viswanath; R D Thulasiraj; G V S Murthy; D L Lamping; S C Smith; M Donoghue; A E Fletcher Journal: Br J Ophthalmol Date: 2005-05 Impact factor: 4.638
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Authors: Anne L Coleman; Steven R Cummings; Fei Yu; Gergana Kodjebacheva; Kristine E Ensrud; Peter Gutierrez; Katie L Stone; Jane A Cauley; Kathryn L Pedula; Marc C Hochberg; Carol M Mangione Journal: J Am Geriatr Soc Date: 2007-03 Impact factor: 5.562