02-25-2017 08:29 AM
In pharmacokinetics, I'm modeling renal and non-renal clearance, and GFR. In a system of linear regression models, I want to test whether a function of the parameter estimates in one model are equal to the parameter estimate in another.
Specifically (in SAS/STAT 14.1):
Proc SYSLin; Identity CL = CLr + CLnr; TvR: Model CL = CLR; TvG: Model CL = GFR; NRvG: Model CLnr = GFR; RvG: Model CLr = GFR; * the following two statements do work; Intercepts: STest TvG.intercept = NRvG.intercept, TvG.intercept = TvR.intercept; SlopeAdd: STest TvG.GFR = NRvG.GFR + RvG.GFR; * the next statement doesnt work cuz its not a linear function; SlopeMul: STest TvG.GFR = RvG.GFR * TvR.CLR; run;