I find a high dispersion, what can be the cause?

If a high spread is found, this can have several causes.
Start an investigation by finding the answers to the following questions:

The functionality of the analysis method

What are the performance characteristics of the method?
Do the performance characteristics meet the criteria mentioned in, for example, the ISO method?

How is the dispersion of other laboratories using the same CRM?
Use the Biosistochart – Analyses Chart function to find out.

The quality of the medium

What is the productivity of the used culture media?
Test the media according to ISO 11133. Take a look at BiosistoStandard to check which control can be used.

The CRM storage at your location

The best stability of CRM is when stored at -80°C.  If stored at a different temperature, stability is not guaranteed.
Is your -80°C freezer constant on the right temperature and does not fluctuate too much?
Do you monitor the temperature constantly and get a signal if there is an exceedance of the temperature?

The training of personnel who performing the analysis

Are the employees adequately trained to perform the method properly?






Biosisto - Quality in Control

Microbiological laboratories should be able to receive reliable analysis without much overhead. A microbiological analyst must be able to focus on the primary activities, for example analysis of the sample material. Quality control should support the analyst in a logical and simple manner. By using modern information technology, process control and quality assurance are designed smarter and more effective.

Biosisto b.v.
Martin Luther Kingweg 3
9403 PA Assen, The Netherlands