polyps | R Documentation |
Data from a placebo-controlled trial of a non-steroidal anti-inflammatory drug in the treatment of familial andenomatous polyposis (FAP).
data("polyps")
A data frame with 20 observations on the following 3 variables.
number
number of colonic polyps at 12 months.
treat
treatment arms of the trail, a factor with
levels placebo
and drug
.
age
the age of the patient.
Giardiello et al. (1993) and Piantadosi (1997) describe the results of a placebo-controlled trial of a non-steroidal anti-inflammatory drug in the treatment of familial andenomatous polyposis (FAP). The trial was halted after a planned interim analysis had suggested compelling evidence in favour of the treatment. Here we are interested in assessing whether the number of colonic polyps at 12 months is related to treatment and age of patient.
F. M. Giardiello, S. R. Hamilton, A. J. Krush, S. Piantadosi, L. M. Hylind, P. Celano, S. V. Booker, C. R. Robinson and G. J. A. Offerhaus (1993), Treatment of colonic and rectal adenomas with sulindac in familial adenomatous polyposis. New England Journal of Medicine, 328(18), 1313–1316.
S. Piantadosi (1997), Clinical Trials: A Methodologic Perspective. John Wiley \& Sons, New York.
data("polyps", package = "HSAUR") plot(number ~ age, data = polyps, pch = as.numeric(polyps$treat)) legend(40, 40, legend = levels(polyps$treat), pch = 1:2, bty = "n")