

leuk(MASS)                                   R Documentation

_S_u_r_v_i_v_a_l _T_i_m_e_s _a_n_d _W_h_i_t_e _B_l_o_o_d _C_o_u_n_t_s _f_o_r _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 of data from 33 leukaemia patients.

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

     wbc: white blood count

      ag: a test result, `"present"' or `"absent"'

    time: survival time in weeks

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

     A data frame with columns:

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

     Cox, D. R. and Oakes, D. (1984) Analysis of Survival
     Data, Chapman  Hall, p. 9.  Taken from

     Feigl, P.  Zelen, M. (1965) Estimation of exponential
     survival probabilities with concomitant information.
     Biometrics, 21, 826-838.

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

     library(survival5)
     data(leuk)
     plot(survfit(Surv(time) ~ ag, data=leuk), lty=2:3, col=2:3)

     # now Cox models
     leuk.cox <- coxph(Surv(time) ~ ag + log(wbc), leuk)
     summary(leuk.cox)

