On this Picostat.com statistics page, you will find information about the retinopathy data set which pertains to Diabetic Retinopathy. The retinopathy data set is found in the survival R package. You can load the retinopathy data set in R by issuing the following command at the console data("retinopathy"). This will load the data into a variable called retinopathy. If R says the retinopathy data set is not found, you can try installing the package by issuing this command install.packages("survival") and then attempt to reload the data. If you need to download R, you can go to the R project website. You can download a CSV (comma separated values) version of the retinopathy R data set. The size of this file is about 17,484 bytes.
A trial of laser coagulation as a treatment to delay
A data frame with 394 observations on the following 9 variables.
numeric subject id
type of laser used:
which eye was treated:
age at diagnosis of diabetes
type of diabetes:
(diagnosis before age 20)
0 = control eye, 1 = treated eye
time to loss of vision or last follow-up
0 = censored, 1 = loss of vision in this eye
a risk score for the eye. This high risk
subset is defined as a score of 6 or greater in at least one eye.
The 197 patients in this dataset were a 50% random sample of the
patients with "high-risk" diabetic retinopathy as defined by the
Diabetic Retinopathy Study (DRS). Each patient had one eye randomized
to laser treatment and the other eye received no treatment,
and has two observations in the data set.
eye, the event of interest was the time from initiation of treatment
to the time when visual acuity dropped below 5/200 two visits in a row.
Thus there is a built-in lag time of
approximately 6 months (visits were every 3 months). Survival times
in this dataset are the actual time to vision loss in months,
minus the minimum possible time to event (6.5 months). Censoring was
caused by death, dropout, or end of the study.
W. J. Huster, R. Brookmeyer and S. G. Self (1989).
Modelling paired survival data with covariates,
A. L. Blair, D. R. Hadden, J. A. Weaver, D. B. Archer, P. B. Johnston
and C. J. Maguire (1976). The 5-year prognosis for vision in diabetes,
American Journal of Ophthalmology, 81:383-396.
coxph(Surv(futime, status) ~ type + trt + cluster(id), retinopathy)
Dataset imported from https://www.r-project.org.