Correlated eye data: Codebook for three datasets
Dataset 1: Percent of normal visual field in 394 eyes of 197 subjects evaluated for glaucoma with Octopus perimetry, measured in a glaucoma consultation service.1,2
Filename: glaucoct.csv
Variables: id, sex (0=male, 1=female), age (in years; range 65-87), eye (1=OD, 2=OS), percent acuity loss (Snellen acuity, transformed to a measure of percent impairment as described by Spaeth,3 range 0-85), aphakic (0=no, 1=yes), diagnosis of hypertension (0=no, 1=yes), percent normal field (in the central 30 degrees, standardized to the normal value at age 65, range 0-132)
Dataset 2. Visual acuity deficits in 888 eyes of 444 patients with retinitis pigmentosa. Cross-sectional data from patients seen at the Berman-Gund Laboratory of the Massachusetts Eye and Ear Infirmary.4,2
Filename: retpigmentosa.csv
Variables: id, autosomal dominant (0=no, 1=yes), autosomal recessive (0=no, 1=yes), sex-linked (0=no, 1=yes [note: referent genetic type is isolate retinitis pigmentosa]), age (years, range 6-80), sex (0=female, 1=male), posterior subscapsular cataract (0=no, 1=yes), eye (0=OS, 1=OD), visual acuity 20/50 or worse (0=no, 1=yes)
Dataset 3. Time to 2-step progression of diabetic retinopathy from fundus photograph grades in the Sorbinil Retinopathy Trial
Filename: srt.csv
Data are from the Sorbinil Retinopathy Trial.5,6 The outcome is 2-step progression in retinopathy from baseline on the ETDRS diabetic retinopathy grading scale. An individual eye will have multiple records if that eye remains free of progression after the other eye in the same person has progressed.
Variables: id, eye (1=OD, 2=OS), start time (in years after randomization), finish time (in years after randomization), progression indicator (0=no, 1=yes), duration of diabetes at randomization (in years), diastolic blood pressure (mm Hg), total glycated hemoglobin (at randomization, %), progression in the other eye at the start of the interval (0=no, 1=yes), sorbinil assignment (0=placebo, 1=sorbinil), cholesterol level (mg/dl).
References
1. Glynn RJ, Seddon JM, Krug JH Hr, Sahagian CR, Chiavelli ME, Campion EW. Falls in elderly patients with glaucoma. Arch Ophthalmol 1991; 109: 205-210.
2. Glynn RJ, Rosner B. Regression methods when the eye is the unit of analysis. Ophthalmic Epidemiol 2012; 19: 159-165.
3. Spaeth EB, Fralick FB, Hughes WF Jr. Estimation of loss of visual efficiency. Arch Ophthalmol 1955; 54: 462-468.
4. Berson EL, Rosner B, Simonoff E. Risk factors for genetic typing and detection in retinitis pigmentosa. Am J Ophthalmol 1980; 89: 763-765.
5. Sorbinil Retinopathy Study Research Group. A randomized trial of sorbinil, an aldose reductase inhibitor, in diabetic retinopathy. Atch Ophthalmol 1990; 108: 1234-1244.
6. Glynn RJ, Rosner B. Methods to quantify the relationship between disease progression in paired eyes. Am J Epidemiol 2000; 151: 965-974.