Making the Most of Participation in Proficiency Testing Schemes

Participation in proficiency testing schemes can bring significant benefits to laboratories. However, the proficiency testing scheme itself cannot cause improvements in laboratory performance. It is up to the participants to use the feedback they receive from the scheme to monitor their performance and to implement improvements where necessary. 

Participation in proficiency testing schemes is an ongoing activity. It is therefore useful to monitor performance over a period of time and to look for trends. Performance over time can be demonstrated statistically by using measures such as RSZ and SSZ (see Section 7.3.4) but as mentioned previously, these can be misleading. It is better to monitor performance scores by plotting them on a 

The data shown in Table 7.3 are from one round of a proficiency testing scheme for the determination of moisture in barley. There are a number of different 

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Making the Most of Participation in Proficiency Testing Schemes... 

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