Guidelines for reporting FOCUS Degradation Kinetics, Ton van der Linden, January 27, 2005

Outline Data Fitting –software package –model and settings –parameters and restrictions –statistics Results –tables –graphs –statistics

Data Data handling –outliers (reasons, statistical analyses,..) –LOQ / LOD –weighting All original values

Data example TimeAmount < LOD 56< LOD Outlier, Grubb’s test,  = 0.05 In analysis as 0.5 * LOD Disregarded in kinetic analysis

Software package identification Examples Berkeley Madonna (2003) ModelMaker 4 (2004) MATLAB 6.51(2003) –Including toolbox Mfit 4.2 (1999)

Package settings Report all user adjustable settings: Integration method Optimisation object function Iteration tolerance

Kinetic model Implementation in software package Concept Schematic (if applicable)

Kinetic model, example Hockey-stick implementation in B.Madonna 8 METHOD RK4 STARTTIME = 0 STOPTIME=100 DT = d/dt (Y) = if time < tb then - k1 * Y else -k2 * Y Init Y = 100. k1 = 0.01 k2 = 0.1 tb = 10

Parameters, etc Report: fixed values initial values of fitted –substances –parameters restrictions on parameters At least two different sets of initial values should be used in order to check for global minimum in optimisation routine

Statistics name of test principle confidence level reference Statistical software package name version reference

Results Table with DT / DegT values –uncertainty –extrapolation beyond experimental data Visual –plot of predicted and fitted values vs time –plot of residuals Statistical –  2 of the fit –uncertainty measures of parameters

visual assessment

Conclusions A report of kinetic analyses contains: all information necessary to allow independent duplication of the results and verification with an alternative package all diagrams and statistical measures underpinning intermediate and final results