Technical data
232 Understanding Your Agilent ChemStation
11 Evaluating System Suitability
Sequence Summary Reporting
Regression Coefficient 253
Standard Deviation (S) 254
Internally Stored Double Precision Number Access 255
This chapter describes what the ChemStation can do to evaluate the 
performance of both the analytical instrument before it is used for sample 
analysis and the analytical method before it is used routinely and to check the 
performance of analysis systems before, and during, routine analysis.
Evaluating the performance of both the analytical instrument before it is used 
for sample analysis and the analytical method before it is used routinely is 
good analytical practice. It is also a good idea to check the performance of 
analysis systems before, and during, routine analysis. The ChemStation 
software provides the tools to do these three types of tests automatically. An 
instrument test can include the detector sensitivity, the precision of peak 
retention/migration times and the precision of peak areas. A method test can 
include precision of retention/migration times and amounts, the selectivity, 
and the robustness of the method to day-to-day variance in operation. A 
system test can include precision of amounts, resolution between two specific 
peaks and peak tailing.
Laboratories which have to comply with: 
• good Laboratory Practice regulations (GLP), 
• good Manufacturing Practice regulations (GMP) and Current Good 
Manufacturing Practice regulations (cGMP), and
• good Automated Laboratory Practice (GALP).
Laboratories are advised to perform these tests and to document the results 
thoroughly. Laboratories which are part of a quality control system, for 
example, to comply with ISO9000 certification, will have to demonstrate the 
proper performance of their instruments. 
The ChemStation collates results from several runs and evaluates them 
statistically in the sequence summary report.
The tests are documented in a format which is generally accepted by 
regulatory authorities and independent auditors. Statistics include: 
• peak retention/migration time, 
• peak area, 
• amount, 
• peak height, 










