RE: NONMEM vs WinNonlin

Dear Bernard NONMEM is command line software for mixed effects modelling, and is commonly used for multiple subject compartmental modelling. There are eight different minimization algorithms that you can use, individually or together. You can usually iterate through model versions, changing initial conditions, boundary conditions, error structure, etc. to achieve convergence. With this tool you should be able to estimate some population parameters where sparse data is available for multiple subjects. Some people prefer to use NONMEM in conjunction with a third party graphical tool, such as Navigator, that includes a menu system, visualization utilities and audit tools. Pheonix WinNonlin is best known for its non-compartmental modelling, but also allows single subject compartmental PKPD modelling. For sparse data it is possible that even the simplest models will not converge. Also note that you are calculating individual rather than population parameters. Pheonix NLME has more similar functionality to NONMEM. The Pheonix products are built around a graphical interface. You may also be interested in looking at Monolix, which is another mixed effects modelling application. Best wishes Chris Chris Campbell Tel. +44 (0) 1249 705 450 | Mobile. +44 (0) 7929 628 349 [email protected] | http://www.mango-solutions.com Mango Solutions, 2 Methuen Park, Chippenham, Wiltshire, SN14 OGB UK