Inter-laboratory comparison is done to assess the extent of likeness in the results produced by various laboratories using the same method.
Likewise, it equates to the performance and evaluation of calibration/test results for a similar item by different laboratories in line with prearranged conditions.
How to Conduct an ISO 17025 Inter-laboratory Studies?
An inter-laboratory comparison is normally composed of:
- Recruitment or selection of laboratories
- Execution according to the plan
- Statistical evaluation of results
When to Conduct an Inter-laboratory Comparison?
- If the formal proficiency testing is unavailable
Laboratories using spikes and other kinds of analytical quality control samples can effectively track the consistency of their performance.
Hence, they should have a very good picture of their internal reproducibility.
If they perform well, it means that their results are accurate.
Laboratories can test from time to time. This is done by exchanging samples with other laboratories and comparing results.
Informal inter-laboratory studies could include exchanging samples on an ad hoc basis.
Meanwhile, formal comparisons could be exercises organized by a third party who circulates performance indicators.
Those formal exercises are a very efficient extension to a laboratory’s internal quality control programme.
To evaluate the degree of similarity of your laboratory’s results in the results of other laboratories, ISO 17025 inter-laboratory comparisons or studies are necessary.
But first, you must know how ISO 17025 itself could prepare you for inter-laboratory comparison.