title: Ordinary differential equation PK/PD models using the SAS macro NLINMIX.
abstract: We describe some theory and recent enhancements for the SAS macro NLINMIX (Wolfinger, R. D. (1993). Laplace's approximation for nonlinear mixed effects models. Biometrika 80:791-795) that enable model calculation to take place within the interaction matrix language SAS/IML (SAS Institute Inc. (1999a). SAS/IML User's Guide Version 7. Cary, NC: SAS Institute Inc.). They provide greater flexibility and scope for the specification and analysis of complex nonlinear mixed models. For example, using data from a frequently sampled intravenous glucose test, we fit a two-compartment kinetics model that has no closed-form representation. It is derived as the solution of a system of ordinary differential equations and specified as such in SAS/IML. Additional details and example NLINMIX code are available in Appendix A.
authors.affiliation: Institute of Gerontology, University of Michigan, Ann Arbor, Michigan 48109-2007, USA. agalecki@umich.edu
authors.forename: Andrzej T
authors.initials: AT
authors.lastname: Galecki
authors.forename: Russell D
authors.initials: RD
authors.lastname: Wolfinger
authors.forename: Oscar A
authors.initials: OA
authors.lastname: Linares
authors.forename: Marla J
authors.initials: MJ
authors.lastname: Smith
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Halter
mesh_terms: D006801:Humans; D016014:Linear Models; D008954:Models, Biological; D010599:Pharmacokinetics