Participant guide
Proficiency testing: what it is and how to participate
A practical starting point for laboratories: understand the comparison, choose a suitable scheme and follow the steps from registration to your report.
What is proficiency testing?
Proficiency testing (PT) enables a laboratory to compare its results with a reference and receive an assessment against criteria defined for the scheme. Participants analyse identical or comparable test items following the provider’s instructions.
This external check helps laboratories identify deviations, monitor performance over time and review the effectiveness of improvements. An outcome relates to the test and conditions assessed and should be considered alongside the laboratory’s other quality controls.
How participation works
- Choose a scheme. Read the technical information, material, parameters, required method where applicable, and schedule.
- Register your laboratory. Complete the form for the service and check administrative and contact details.
- Receive the sample and instructions. Check identification and condition on receipt; report any problems before analysis.
- Perform the test. Follow storage, preparation and method instructions. Organise the work to represent routine laboratory practice.
- Submit your result. Use the specified units and reporting basis, check the entered value and meet the communicated deadline.
- Review the report. Examine your result, the reference and assessment; document any investigation and improvement actions.
How to choose a suitable scheme
Start with the test performed in your laboratory and compare it with the scheme information. The parameter name alone is not enough.
- Matrix and material: soil, water, filters or fibres should be relevant to the work you want to assess.
- Measurand and range: check the quantity being assessed, units and expected range when stated.
- Method and technique: check compatibility with your equipment and the scheme instructions.
- Timing: consider dispatch, staff availability and the result submission deadline.
- Assessment: read the statistical criteria and expected report contents.
If any detail is unclear, contact Microanalitica before registering. Refer to the programme and current scheme information for dates, prices and availability.
Find your testing area in the programme
Follow these links to Microanalitica scheme pages to check their characteristics and participation arrangements.
PT or Check Sample Test?
PT follows a programme with participation and result collection dates defined for the round. It supports a planned comparison with other participants.
Check Sample Test (CST) uses surplus samples from a set prepared for an earlier proficiency test, subject to availability. It provides an additional check, for example after a method adjustment or at another point in time.
For CST, check the batch, availability and scheme-specific criteria. In the website’s SETA and AIR models, new results admitted to the calculation contribute to updates of the statistical reference. Each report records the assessment for the processed version; previously issued copies remain archived.
What participants receive
- The test material specified for the scheme and instructions for its use.
- Result submission instructions, required information and applicable deadlines.
- A report containing the participant’s result, statistical references and the assessment specified for the scheme.
- Access to reports published for their laboratory in the client area.
For CSTs managed using the website’s report generator, reports are produced in Italian and English as separate PDF files. Once approved by the administrator, they are published in the client area and emailed to the associated recipient. The PDFs remain archived.
The participant code identifies your result in the comparison while keeping other laboratories’ identities confidential.
Understanding the assessment
The assigned value is the reference against which your result is compared. The standard deviation for proficiency assessment sets the scale of the deviation; the uncertainty of the assigned value describes the precision of the reference estimate.
The score depends on the scheme: z, z′ and zp use different calculations. Check the report for the index used, its rounding rules and the criteria determining the outcome. Do not automatically transfer one scheme’s formula to another.
A warning or unsatisfactory outcome calls for investigation: check transcription, units, preparation, method and equipment. Record your investigation and consider a subsequent check of the effectiveness of any action taken.
Questions before registering
Does participation confer accreditation?
No. Participation provides evidence of performance and can support a quality control system. Accreditation is a separate process.
Must I report my measurement uncertainty?
Provide the information requested for the particular scheme. Your laboratory’s uncertainty and the uncertainty of the assigned value are different quantities: including the latter in a report does not mean you must declare the former.
Can I choose any CST batch?
Your choice depends on availability and suitability for the test. Check the scheme information and allocation instructions before proceeding.
How do I start?
Read the programme, open the relevant scheme page and follow the registration link. For technical questions, email info@microanalitica.eu with your matrix, parameter and method.
Technical references
ISO/IEC 17043 addresses the competence of PT providers. ISO 13528 covers statistical methods for PT. For each Microanalitica scheme, the applicable instructions and report criteria remain the operational reference.