

gehan(MASS)                                  R Documentation

_R_e_m_i_s_s_i_o_n _T_i_m_e_s _o_f _L_e_u_k_a_e_m_i_a _P_a_t_i_e_n_t_s

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

     A data frame from a trial of 42 leukaemia patients.
     Some were treated with the drug 6-mercaptopurine and
     the rest are controls.  The trial was designed as
     matched pairs, both withdrawn from the trial when
     either came out of remission.

_A_r_g_u_m_e_n_t_s_:

    pair: label for pair

    time: remission time in weeks

    cens: censoring, 0/1

   treat: treatment, control or 6-MP

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

     This data frame contains the following columns:

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

     Cox, D. R. and Oakes, D. (1984) Analysis of Survival
     Data.  Chapman  Hall, p. 7. Taken from

     Gehan, E.A. (1965) A generalized Wilcoxon test for com-
     paring arbitrarily single-censored samples.  Biometrika
     52, 203-233.

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

     library(survival5)
     data(gehan)
     gehan.surv <- survfit(Surv(time, cens) ~ treat, data=gehan,
          conf.type="log-log")
     summary(gehan.surv)
     survreg(Surv(time, cens) ~ factor(pair) + treat, gehan, dist="exp")
     summary(survreg(Surv(time, cens) ~ treat, gehan, dist="exp"))
     summary(survreg(Surv(time, cens) ~ treat, gehan))
     gehan.cox <- coxph(Surv(time, cens) ~ treat, gehan)
     summary(gehan.cox)

