Guidelines for reporting

1
Guidelines for reporting

• FOCUS Degradation Kinetics, Ton van der Linden,
  January 27, 2005

2
Outline

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

3
Data

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

4
Data example
Time Amount
0 100
1 10
2 71
4 50
7 30
14 9
28 lt LOD
56 lt LOD
Outlier, Grubbs test, ? 0.05
In analysis as 0.5 LOD
Disregarded in kinetic analysis
5
Software package identification

• Examples
• Berkeley Madonna 8.0.1 (2003)
• ModelMaker 4 (2004)
• MATLAB 6.51(2003)
• Including toolbox Mfit 4.2 (1999)

6
Package settings

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

7
Kinetic model

• Implementation in software package
• Concept
• Schematic (if applicable)

8
Kinetic model, example

• Hockey-stick implementation in B.Madonna 8
• METHOD RK4
• STARTTIME 0
• STOPTIME100
• DT 0.001
• d/dt (Y) if time lt tb then - k1 Y else -k2
  Y
• Init Y 100.
• k1 0.01
• k2 0.1
• tb 10

9
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

10
Statistics

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

11
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

12
visual assessment
13
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