/* "Retrospective Population-Based Analysis of the Dose-Response (Fecal Fat Excretion) Relationship of Orlistat in Normal and Obese Volunteers",(1994),Clinical Pharmacology & Therapeutics,56:82-85. Zhi, et al. Model: % Fecal Fat Excretion = Y = B0 + (B1*X / (B2+X)) where: B0 = % Excretion on Placebo B1 = Maximal effect (As change from placebo) B2 = ED50 (Dose Producing 50% of maximal effect) */ options nodate nonumber; data _0_; input ffe @@; odd=0; cards; 24 18 13 12 11 10 9 8 8 8 8 8 8 7 7 7 7 7 7 6 6 6 6 6 6 6 6 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 0 ; data _30_; input ffe @@; odd=30; cards; 42 34 28 21 18 18 ; data _60_; input ffe @@; odd=60; cards; 57 35 35 24 18 17 15 14 13 10 6 2 ; data _120_; input ffe @@; odd=120; cards; 28 21 20 18 13 8 ; data _150_; input ffe @@; odd=150; cards; 38 22 21 20 20 19 18 18 17 17 16 16 15 15 14 14 13 13 12 12 11 10 9 8 ; data _240_; input ffe @@; odd=240; cards; 40 39 36 31 30 28 28 27 23 19 18 16 13 12 10 8 5 2 ; data _300_; input ffe @@; odd=300; cards; 46 36 28 25 20 ; data _480_; input ffe @@; odd=480; cards; 48 45 40 39 38 37 35 32 27 25 23 22 14 ; data _600_; input ffe @@; odd=600; cards; 47 37 31 23 20 18 ; data _1200_; input ffe @@; odd=1200; cards; 20 28 33 34 38 ; data all; set _0_ _30_ _60_ _120_ _150_ _240_ _300_ _480_ _600_ _1200_; proc nlin; parms e0=5.29 emax=27.1 ed50=98.1; model ffe=e0+((emax*odd)/(ed50+odd)); der.e0=1; der.emax=odd/(ed50+odd); der.ed50=-((ed50+odd)**-2)*(emax*odd); output out=nlinout p=yhat; run; symbol1 c=black i=spline l=1; symbol2 c=black v=diamond; proc gplot; plot yhat*odd=1 ffe*odd=2 / overlay frame haxis=0 to 1200 by 200 vaxis=0 to 60 by 10; title 'Orlistat Dose-Response -- Nonlinear Regression'; run; quit;