polyps                 package:HSAUR                 R Documentation

_F_a_m_i_l_i_a_l _A_n_d_e_n_o_m_a_t_o_u_s _P_o_l_y_p_o_s_i_s

_D_e_s_c_r_i_p_t_i_o_n:

     Data from a placebo-controlled trial of a non-steroidal
     anti-inflammatory   drug in the treatment of familial andenomatous
     polyposis (FAP).

_U_s_a_g_e:

     data("polyps")

_F_o_r_m_a_t:

     A data frame with 20 observations on the following 3 variables.

     '_n_u_m_b_e_r' number of colonic polyps at 12 months.

     '_t_r_e_a_t' treatment arms of the trail, a factor with  levels
          'placebo' and 'drug'.

     '_a_g_e' the age of the patient.

_D_e_t_a_i_l_s:

     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.

_S_o_u_r_c_e:

     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.

_E_x_a_m_p_l_e_s:

       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")

