Phenobarb package:nlme R Documentation _P_h_e_n_o_b_a_r_b_i_t_o_l _K_i_n_e_t_i_c_s _D_e_s_c_r_i_p_t_i_o_n: The 'Phenobarb' data frame has 744 rows and 7 columns. _F_o_r_m_a_t: This data frame contains the following columns: _S_u_b_j_e_c_t an ordered factor identifying the infant. _W_t a numeric vector giving the birth weight of the infant (kg). _A_p_g_a_r an ordered factor giving the 5-minute Apgar score for the infant. This is an indication of health of the newborn infant. _A_p_g_a_r_I_n_d a factor indicating whether the 5-minute Apgar score is '< 5' or '>= 5'. _t_i_m_e a numeric vector giving the time when the sample is drawn or drug administered (hr). _d_o_s_e a numeric vector giving the dose of drug administered (mug/kg). _c_o_n_c a numeric vector giving the phenobarbital concentration in the serum (mug/L). _D_e_t_a_i_l_s: Data from a pharmacokinetics study of phenobarbital in neonatal infants. During the first few days of life the infants receive multiple doses of phenobarbital for prevention of seizures. At irregular intervals blood samples are drawn and serum phenobarbital concentrations are determined. The data were originally given in Grasela and Donn(1985) and are analyzed in Boeckmann, Sheiner and Beal (1994), in Davidian and Giltinan (1995), and in Littell et al. (1996). _S_o_u_r_c_e: Pinheiro, J. C. and Bates, D. M. (2000), _Mixed-Effects Models in S and S-PLUS_, Springer, New York. (Appendix A.23) Davidian, M. and Giltinan, D. M. (1995), _Nonlinear Models for Repeated Measurement Data_, Chapman and Hall, London. (section 6.6) Grasela and Donn (1985), Neonatal population pharmacokinetics of phenobarbital derived from routine clinical data, _Developmental Pharmacology and Therapeutics_, *8*, 374-383. Boeckmann, A. J., Sheiner, L. B., and Beal, S. L. (1994), _NONMEM Users Guide: Part V_, University of California, San Francisco. Littell, R. C., Milliken, G. A., Stroup, W. W. and Wolfinger, R. D. (1996), _SAS System for Mixed Models_, SAS Institute, Cary, NC.