What is Meant by 'Manual Integration'?

As a chromatographer of many years my understanding of the term 'manual integration' is that you view an individual chromatogram using chromatography software and use the mouse to move the cursor on the screen so as to adjust the peak start and/or peak end, resulting in the integration which you feel is most suitable to quantify that particular peak. It is a contentious procedure, since it is very susceptible to falsification. Small adjustments can make the difference between a passing or failing result.

If this sounds familiar then you should be aware that this is not always what is meant when people use the terminology, particularly regulatory inspectors. It is now commonly used to describe the process of reintegrating, i.e. changing the integration parameters from the original settings and reprocessing the chromatograms. It may be used even if the same integration method and thus parameters have been applied automatically by the software, and sample and standard chromatograms are all integrated in the same way.

A distinction between the terms 'manual intervention' and manual integration' has been suggested by R McDowall in his excellent article, 'Questions of Quality: Where Can I Draw The Line?' (a previous post under MTS Recommends...). I think it would be advisable to include this distinction both in a policy on manual integration and also in the training programme for chromatographers.

MTS are offering a new course, 'How to Improve Data Integrity in the Pharma Lab', as part of our Laboratory Data Integrity programme in which the topic of chromatographic integration, including manual integration, will be explored fully. Visit the MTS website for more information.

  Tweet