FAQ

ISO/IEC 17043 is available for accreditation of proficiency testing providers which has been developed by ISO and Pasargad Quality Pioneers (PQP) designs and implements its program in accordance with this standard. Statistical analysis is being done in accordance with ISO 13528 international standard.

Yes. Considering the type of the programs, technical advisors are chosen from the relevant industries based on the required knowledge and experience for the programs.

For each program, technical specifications and registration form are available at programs menu in the website which includes type of samples and related dates of the program. Participants should complete the registration form and send it back to us via email info@pqp-pt.cpm or fax no.: +98(21)88546443

In order to ensure bout the confidentiality of results, a unique code is assigned to all the participants in a program. This code keeps the identities of the participant laboratories as confidential. Only Pasargad Quality Pioneers (PQP), the participant laboratory and the legal authorities in necessary cases are informed about the identities of the participants.

Interval for participation in proficiency testing programs depends on several factors such as other used quality control tools, volume of work and risks associated with the laboratory measurements which can be different for every laboratory. In conclusion, every laboratory might have different needs and they select the interval for participation in PTs based on those needs.

The fees for participation in programs are defined in registration forms and proficiency testing programs specifications. Terms of payment are also described in registration form.

There are different sources for PT samples depending on every program specifications. Test samples are selected in a way which will be as similar as possible to the participant laboratories routine samples. However in some case and in order to maintain the required homogeneity and stability, test samples are supplied in forms of reference materials and pure standards.

Participants should perform the test according to their own method unless PQP specifies the test method.

PQP defines the deadline for results submission and sends it to the participants with the samples.

Participants should send their results in the specified period so their results will be considered in statistical analysis and program report. Received results after the deadline are not considered in the final report and only an individual performance evaluation report will be prepared for the participant and one copy of the final report will also be sent to them for information.

ISO 13528 standard “Statistical methods for use in proficiency testing by interlaboratory comparisons” has defined the method for establishment of assigned value.

The assigned value is a value which is considered to be the best estimate of the true value. The chosen method for establishment of the assigned value is different for different programs and the details are described in the associated program final report.

PT data can be used in top-down approach for estimation of measurement uncertainty. This approach is described in three documents:

  • NORDTEST Report TR 537 'Handbook for Calculation of Measurement Uncertainty in Environmental Laboratories'
  • ISO/TS 19036 'Microbiology of food and animal feeding stuffs - Guidelines for the estimation of measurement uncertainty for quantitative determinations'
  • Eurolab Technical Report No. 1/2007, March 2007 ‘Measurement uncertainty revisited: Alternative approaches to uncertainty

SDPA is an indication of acceptable differences between the laboratory result and the assigned value. The method for establishment of SDPA is different for every program according to type of the program and the test material.

Once the assigned value for the parameters under test has been established, participant laboratories are assessed on the difference between their result and the assigned value, with this difference being represented by a performance score, normally the z-score. The advantages of a z-score are:

  • Results can be expressed in a form that is relatively easy to interpret and understand
  • Results can be summarized in graphical or tabular form to depict overall performance
  • A performance score allows participants to directly compare their own result with others
  • If consistent statistical values are applied, a performance score enables participants to monitor and trend their own performance over time.

Z-score of the participants is calculated using the following formula:

Z = (x - µ)/SDPA

In which:

x: participant result

µ: assigned value

SDPA: Standard deviation for proficiency assessment

For the purposes of performance assessment for a single round, z scores are interpreted as follows:

  • |Z|
  • 2<|Z| < 3: Questionable result
  • |Z|>3: unsatisfactory Result

A poor result in a single round is not an indication of the laboratory performance and neither a good result in a single round. Ideally, PT results should be monitored over time to detect unusual biases and unacceptable results which are the indicators of poor performance.

Final report will be available in a period of almost one month after the results submission deadline in the website. If it is requested by the laboratories, paper copies of reports will also be sent upon request with an additional charge.

Contact Information

Address : Apt. 11-3rd floor- No.74- Shahrtash St. North Sohrevardi St.- Beheshti St.- Tehran- Iran

Tel:
02188546426-7
02186031802
02186031813
Fax : 02186030627

Postal Code: 123542336437
Email : ino@pqp-pt.com
Website : Pishgaman Quality Control