These are the data of the Collaborative Initial Glaucoma Treatment Study (CIGTS_BinCont), a randomized clinical trial designed to compare the effects of surgery and medicine on intraocular pressure (IOP). Elevated IOP is an important risk factor for glaucoma, which is an occular disorder that leads to impaired vision. S and T are IOP at months \(12\) and \(96\), respectively. A total of \(N=228\) patients had IOP measured at both time points of interest. The continuous S and T were dichotomized in the following way: \(S=1\) if IOP at month \(12\) is \(<18\) mmHg and \(S=0\) if IOP at month \(12\) is \(>=18\) mmHg (and similarly for T).
Acknowledgment
David Musch (Coordinating Center Director) and Brenda Gillespie (Study Statistician) are gratefully acknowledged for providing data from the Collaborative Initial Glaucoma Treatment Study (CIGTS_BinCont).
data(CIGTS_BinCont)A data.frame with \(228\) observations on \(4\) variables.
CenterThe center where the patient was treated.
TreatThe treatment indicator, coded as \(-1\) = medical treatment and \(1\) = surgery.
IOP_12The continuous IOP level \(12\) months following randomization.
IOP_12_BinThe dichotomized IOP level \(12\) months following randomization.
IOP_96_BinThe dichotomized IOP level \(96\) months following randomization.
Musch, D. C., Lichter, P., R., Guire, K. E., Standardi, C. L., & CIGTS_BinCont Investigators (1999). The Collaborative Initial Glaucoma Treatment Study (CIGTS_BinCont): Study design, methods, and baseline characteristics of enrolled patients. Ophthalmology, 106, 653-662.