The Diabetic Retinopathy Study (DRS) was performed to determine whether the onset of blindness in 197 high-risk diabetic patients could be delayed by laser treatment. The treatment was administered to one randomly-selected eye in each patient, leaving the other eye untreated. Thus, there are 394 observations, which are clustered by patient since the level of risk will tend to vary between patients. A failure occurred when visual acuity dropped to below 5/200. All patients had a visual acuity of at least 20/100 at the beginning of the study.
A data frame with 394 rows and 8 columns. There are two rows for each subject, one row for each eye:
unique identifier for each subject
subject's eye, where 1=right and 2=left
the observed follow-up time
outcome at the end of the observation period, where 1=blindness and 0 indicates censorship
a binary covariate, where 1=treated or 0=untreated
age (in years) at the onset of diabetes
type of laser used for treatment, where 1=xenon, 2=argon
type of diabetes, where 1=juvenile (age at dx < 20) and 2=adult
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.