Work

Criteria for using proficiency test results for estimation of measurement uncertainty: feed analysis example

Year: 2017

Type: article

Abstract: On the basis of long-standing proficiency testings (PTs) for the small number of PT participants p (7 ≤ p ≤ 30), laboratory bias and uncertainty were calculated by applying inter-laboratory experimental approaches. Uncertainty was estimated in two ways, according to Eurolab TR No 1/2007 and Nordtest TR 537 (2012). In the case of 24 tested feed components (basic nutrients, macro- and microelements, undesirable elements and some feed additives including vitamins A and E, lysine, threonine, methionine and urea) in the large variety of feed samples, differences between the expanded uncertainties calculated according to Eurolab TR No 1/2007 and Nordtest TR 537 did not exceed 1.4 % for all tested feed and analytes in wide concentration ranges. In order to get a reliable evaluation of bias and uncertainty, minimum of 6 PT rounds and a sufficient number of laboratories participating (p ≥ 10) are recommended. When the above parameters are applied and the standard deviation of the bias s bias ≤ 5 %, the expression s bias 2 /n can be omitted while calculating bias. Generally, both approaches fit the purpose of feed evaluation and the calculated uncertainties can be used for compliance assessment.

Source: Accreditation and Quality Assurance

DOI: 10.1007/s00769-017-1252-1

Authors: Waldemar Korol, Jolanta Rubaj, Grażyna Bielecka, Sławomir Walczyński, Joanna Reszko-Zygmunt, Ryszard Dobrowolski

Institutions: National Research Institute of Animal Production, Maria Curie-Skłodowska University

Language: English

Topic: Scientific Measurement and Uncertainty Evaluation

Subfield: Instrumentation

Field: Physics and Astronomy

Domain: Physical Sciences

SDG: Zero hunger

Open Access status: hybrid

Estimated APC paid: $3,890