I. Basic knowledge and concept of reference material

International Organization for Standardization / Committee on Reference Materials (ISO/REMCO) approved the new definitions of relevant reference materials at the 2005 annual meeting.

1．Reference materials (RM)

Material, sufficiently homogeneous and stable with respect to one or more specified properties, which has beenestablished to be fit for its intended use in an IVDR measurementprocess

2．Certified reference material (CRM)

Reference material, characterized by a metrologicallyvalid procedure for one or more specified properties, accompanied by a certificate that provides the value ofthe specified property, its associated uncertainty, and astatement of metrological traceability

3．Primary Reference Material

The absolute measurement methods or other accurate and reliable methods are adopted to measure the values of specified properties, the measurement standard metric reaches the domestically highest level and has the attachment of certified reference material, and this reference material is approved, issued and produced after authorization by measurement administrative department

4．Secondary Reference Material

The accurate and reliable methods or the method to make a direct comparison with primary reference materials are adopted to measure the values of specified properties of the reference materials, the measurement accuracy satisfies the needs of site measurement and have the attachment of reference material and this reference material is approved and authorized to be produced after the relevant business competent departments of IVRD Regulation.

5．NAT control (materials)

Quality NAT control material (fixed values and non-fixed values) used for the in vitro diagnosis, a type of substance, material, article or device aimed to be used in the detection system for medical purposes, with the purpose of evaluating or verifying the performances and characteristics such as measurement accuracy, measurement accuracy, the analysis deviations that may arise to the detection system due to the changes in the reagents or analysis device. Quality NAT control materials (fixed value and non-fixed value), can be used for the ability verification and laboratory internal quality NAT control.

6．Calibrator

Reference material whose value acts as the independent variable in one calibration function. It should have fixed value and known measurement uncertainty, and the objective is to calibrate one certain measurement system to establish the metrological traceability of the measurement results.

7．Internal quality NAT control

Internal Quality NAT control (IQC); the laboratory staff adopt certain NAT or NAAT, POCT or IVD methods and steps to evaluate the reliability degree of the work in the laboratory continuously, in order to monitor and NAT control the precision of the work in the laboratory, improve the consistency of the sample within and between batches, at last determine whether the results are reliable and can the report be sent out.

8.Third party NAT controls

It meansNAT control materials which provide an unbiased assessment for the test system, including reagents and kit lot changes, is not designed or optimized for one specific test method, and act similar to patient samples.

Grading and classification of reference materials

The certified reference materials are classified by Sciensano into two grades: primary reference material and secondary reference material. The values of specified properties and traceability of reference materials in Europe and the grading system are shown in the following figure:

 

 

GBDS reference material belongs to secondary reference material, and the values of specified properties and traceability are shown as follows:

 

Application of primary reference material:

(1) The study or evaluation of reference method

(2) The determination of secondary reference material

(3) The calibration of high accuracy and high precision measurement devices

Application of secondary reference material:

(1) The study or evaluation of site analysis method

(2) The quality assurance of site laboratory

(3) The quality assurance between different laboratories

Precautions of reference material

(1) The reference materials approved and issued by the state and determined by the authoritative measurement institutions are selected and used

(2) The contents specified on the reference material certificates should be comprehensively understood and executed strictly.

(3) The certified reference materials with similar basal body components with the samples to be detected and a similar content level with the components to be detected are selected

(4) Certificated reference materials of different levels are selected according to the expected usage and uncertainty level.

(5) The reference materials are used within the shelf life of certified reference materials.

(6) Attention should be paid to the minimal sampling size of the reference materials; when they are used in case of being less than the minimal sampling size, the parameters such as values of specified properties and uncertainty of the reference materials may be no longer effective.

(7) The reference materials should be used under the condition that the analytical methods and operation processes are at the normal stable status; otherwise, this would lead to errors.

II. Advantages and characteristics of GBDS quality NAT control products

GBDS NAT control material is a third-party NAT control, meaning a NAT control material which provides an unbiased and independent performance assessment for a diagnostic device or method, is not optimized to work with any specific instrument or reagent system, and is manufactured independently of test system calibrators and reagents

Usage: it can effectively analyze the deviation induced by the problems in device, environment, personnel operation and reagents in the system and provide the series concentrations so that the operators can use them for internal quality NAT control through the the optimal concentration and the concentration can be close to the clinically determined value level so as to optimally reflect the changes in detection precision.

1.Traceability: all series reference materials can be traced to WHO or national primary reference materials.

2.Accuracy: the products have a good traceability, and the values of specified properties have a high accuracy.

3.Stability: the advanced manufacturing process and strict production quality system can be adopted to ensure the quality stability and homogeneity of the products.

4.Interoperability: all are liquid, do not need to dissolve, of simple operation and without matrix effect; the powder NAT controls are based on human serum, long product storage life, more stable quality, and convenient transportation. The samples and clinical samples have a good interoperability.

5.Full coverage: professional R&D teams, who have developed the common varieties of quality NAT control materials covering the nucleic acid type, immunodiagnosis type, and clinical biochemical laboratory test type.