Allergen Component Testing
UKAS Schedule of Accreditation
Diagnosis and management of allergic disease
PURPOSE OF PROGRAMME:
Allergy and Immunodeficiency EQA scheme
MATERIAL PROVIDED: Liquid format. Normal and pathological human serum
DISTRIBUTIONS PER YEAR: 6
SAMPLES PER DISTRIBUTION: 2 (only 1 to be tested on ISAC)
FREQUENCY OF DISTRIBUTION: Every two months. A maximum of nine recombinant allergen specific IgE tests will be analysed on each specimen for the Recombinant Allergen element of the scheme. All 112 allergens currently available for the ISAC method are to be analysed for the ISAC element (only relevant to the first specimen)
PROGRAMME OF ANALYSIS:
Data entry is via the web for the submission of results. ISAC results are submitted via the web in CSV file format. Data analysis is commenced 21 days after sample despatch. Late returns are only accepted for the Recombinant Allergen element of the scheme and will contribute to the laboratory's cumulative performance statistics. No late result for the ISAC element will be accepted.
Recombinant Allergens: Analysis by grade shows the overall response and the method-specific responses ISAC: Analysis by units shows the overall response and the method-specific responses Analysis of the quantitative responses for both elements in Units shows the All Laboratory Trimmed Mean (ALTM) with truncation at 2SD, SD, and CV%. Reports show method-specific statistics. Individual laboratory performance is expressed in terms of MRBIS, SDBIS, and MRVIS, the DV for calculation of VI being taken from the ALTM. Chosen Coefficient of Variation for Recombinant Allergen Specific Components (IgE) is 15%
Cumulative performance scored are based on the quantitative response with MRVIS scoring over a running window of twelve samples over twelve months
Performance assessment is allergen specific. Quantitative performance is assessed for each allergen, and is over a running period of 6 distributions containing that allergen (12 months). The overall quantitative performance is expressed as the OMRVIS, the mean of all the individual allergen specific MRVIS. The semiquantitative Grades are assessed by MI scoring in relation to the Consensus Designated Response (CONDR). (For this purpose, grades 0 and 1 are considered as NEGATIVE, and grades 2 - 6 are considered as POSITIVE). Overall MIS (OMIS) greater than 3 will also be considered as poor performance.
PERSISTENT POOR PERFORMANCE:
Defined as being in the poor performance category for two or more successive distributions
Immunology, Immunochemistry & Allergy (IIA)
The External Quality Assessment Scheme for Immunology, Immunochemistry & Allergy (IIA) was founded in 1982 by Dr Anthony Milford Ward at Northern General Hospital, Sheffield. In 1982 the Service became known as the UK National External Quality Assessment Service for Immunology, Immunochemistry & Allergy. UK NEQAS IIA is part of the Sheffield Teaching Hospitals NHS Foundation Trust.