fractionation           package:DPpackage           R Documentation

_B_r_i_t_i_s_h _I_n_s_t_i_t_u_t_e _o_f _R_a_d_i_o_l_o_g_y _F_r_a_c_t_i_o_n_a_t_i_o_n _S_t_u_d_i_e_s

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

     The British Institute of Radiology (BIR) conducted two large-scale
     randomized clinical trials to assess the effectiveness of
     different radiotherapy treatment schedules for cancer of the
     larynx and pharynx. The cambined data come from 858 subjects with
     laryngeal squamous cell carcinomas and no involvement of asjacent
     organs. These data have been described and analyzed by Rezvani,
     Fowler, Hopewell, and Alcock (1993).

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

     data(fractionation)

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

     A data frame with 858 observations on the following 6 variables.

     '_r_e_s_p_o_n_s_e' Three-year local control 1 (0 no control).

     '_d_o_s_e' Total dose (grays).

     '_d_f' Total dose x dose/fraction.

     '_t_i_m_e' Total time of treatment (days).

     '_k_t_2' Tumor status (indicators for 2nd level of factor).

     '_k_t_3' Tumor status (indicators for 3rd level of factor).

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

     Three-year local control - meaning no detection of laryngeal
     carcinoma  within three years after treatment - is the binary
     response, coded as 1  if local control is achieved and 0
     otherwise. For this data set, three-year local control is achieved
     for 69 a total dose of radiation is administered in fractions over
     a treatment period. The dose per fraction df is measured in grays
     (Gy), the length of treatment period time is measured in days, and
     the number of fractions of the dose is nf. Tumors are classified
     by stage (i.e., the extent of  invasion), into three groups. This
     categorical covariate is coded by two indicator variables kt2 and
     kt3, which are defined by kt2=1 (kt3=1) is the tumor is stage II
     (stage III) and zero otherwise.

     Chappell, Nondahl and Fowler (1995) argued that the tumor stage,
     the total dose, the  total time, and the interaction of the total
     dose per fraction are the  relevant explanantory variables
     affecting probability of local control.

_R_e_f_e_r_e_n_c_e_s:

     Chappell, R., Nondahl, D.M., and Fowler, J.F. (1995) Modelling
     Dose and Local Control in Radiotheraphy. Journal of the American
     Statistical Asso- ciation, 90: 829 - 838.

     Newton, M.A., Czado, C., and Chappell, R. (1996) Bayesian
     inference  for semiparametric binary regression. Journal of the
     American Statistical  Association, 91, 142-153.

     Rezvani, M., Fowler, J., Hopewell, J., and Alcock, C. (1993) 
     Sensitivity of Human Squamous Cell Carcinoma of the Larynx to
     Fractionated Radiotherapy. British Journal of Radiology, 66: 245 -
     255.

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

     data(fractionation)
     ## maybe str(fractionation) ; plot(fractionation) ...

