In the clinical laboratory, Quality Control (QC) refers to the process of detecting analytical errors to ensure both the reliability and accuracy of patient test results. Poor performance can result in misdiagnosis, delayed/inappropriate treatment, increased costs and may even be potentially life threatening for the patient. Third party controls offer a better solution to ensure optimum performance and accuracy, read on to learn how.
Types of control material
Dependent controls refer to any control material that has been produced by the instrument or reagent manufacturer for use on a specific test system. Such controls are often manufactured from the same raw materials as the calibrator, making them less sensitive to subtle changes in performance.
As dependent controls are generally optimised for use with the manufacturer’s test system, these controls can mask weaknesses, and therefore, are increasingly considered less effective than independent controls.
Semi-dependent control material, although produced independently of the instrument or reagent, is often supplied or recommended by the instrument/reagent manufacturer. It is this manufacturing relationship between the two that requires close scrutiny when considering if these controls are fit-for-purpose.
Although the control material is not produced by the instrument manufacturer, it is produced according to their exact specifications and therefore, optimised to work with a specific platform.
Independent or third party quality control material has not been designed or optimised for use with any instrument, kit or method. This complete independence enables the quality control material to closely mirror the performance of patient samples, and in doing so, provide an unbiased, independent assessment of analytical performance across multiple platforms.
Benefits of using third party controls
Third party controls have been designed to deliver an independent, unbiased assessment of performance with any instrument or method helping you gain accreditation. Below are some of the key benefits of third party controls:
- Values assigned using a large number of independent laboratories ensuring statistically valid targets.
- Highly consolidated controls allow for space, time, and ultimately, cost savings.
- Boosted shelf life ensures continuity of supply and reduced costs
- Reduced preparation times by removing the need for multiple instrument controls
Third party controls are growing in popularity across the globe. More and more laboratories are beginning to use third party controls as part of their daily QC strategy. The benefits of such controls are widely accepted and recommended by both key opinion leaders and regulatory bodies in the field of Quality Control.
“Use of independent third party control materials should be
considered, either instead of, or in addition to, any control
materials supplied by the reagent or instrument manufacturer”
ISO 15189:2012 Section 18.104.22.168
ISO 15189:2012 Medical Laboratories – Requirements for Quality and Competence
The benefit of running third party controls in your laboratory cannot be underestimated. The following case studies highlight their many benefits and how they have helped laboratories across the world to provide more accurate and reliable test results.
Case Study One: Identifying Lot-to-Lot Variability with Third Party Controls
A laboratory in the UK contacted Randox Technical Services, reporting higher than expected QC results for
Thyroglobulin. When using a third party control (Acusera Immunoassay Premium Plus) the results were four
times higher on their main analyser compared to other systems. However, when they ran the instrument
manufacturer’s control alongside the third party control it did not show the same problem.
After reviewing EQA data, the Technical Services team confirmed there was a significant difference in results
compared to other instruments, and set about helping the laboratory troubleshoot. After an exhaustive
review of procedures and processes, the customer contacted the instrument manufacturer, who advised of a
positive bias with several batches of reagent, including the batch the laboratory was using.
Conclusion: By using a third party control the laboratory was able to detect a shift in results after changing
reagent batch that the instrument manufacturer’s control did not.
Case Study Two: Overcoming Instrument Errors with Third Party Controls
A laboratory using the Acusera Assayed Chemistry Premium Plus control contacted Randox Technical Services
after observing a consistent negative bias for ALT which was not replicated by the instrument control. They
had previously contacted their instrument manufacturer who advised that the problem was with the control
and not the reagent or instrument.
Randox investigated the problem and demonstrated that patient results were also wrongly reported low. This
later led the instrument manufacturer to recommend a wash stage to eliminate any interference.
Conclusion: The use of a third party control in this instance enabled the identification of a procedural error
with the instrument that the recommended control did not.
Benefits of Acusera True Third Party Controls
Explore the benefits of Randox Acusera third party controls below.
We take quality seriously, that’s why all QC products are manufactured to the highest possible standard delivering control products of unrivalled quality.
Regular shifts in QC results after a change in reagent batch can be both costly and frustrating for many labs, resulting in a frequent need to reassign target values. Designed to be commutable, the Acusera range of Internal Quality Controls will react to the test system in a manner as close to the patient sample as possible, helping you meet ISO 15189 requirements while ultimately ensuring accurate & reliable instrument performance.
ISO 15189 states that labs should “use quality control material that reacts to the examining system in a manner as close as possible to patient samples”.
All controls for use with immunoassay/immunology based methods are manufactured using only 100% human components demonstrating our commitment to quality and eliminating costly QC shifts when reagent batch is changed.
Many manufacturers ‘cut corners’ or take shortcuts in an attempt to keep costs down. This often results in unrealistic values, parameter imbalances, a frequent lack of differentiation between levels and ultimately in controls that do not completely cover the clinical range. In many situations these inadequacies force laboratories to purchase additional and often expensive low or high level controls. For example Troponin levels in the level 1 control from some manufacturers do not adequately cover the cut-off levels used in diagnosis. This often results in the need for additional controls to cover these lifesaving concentrations. The levels of Troponin I and Troponin T in our Cardiac and Liquid Cardiac controls are in line with internationally recommended levels.
Randox also employs easy to use colour-coded packaging to help distinguish between different levels and reduce costly mix-ups.
Employing thousands of independent laboratories worldwide, our unique value assignment process ensures highly accurate target values for an extensive range of instruments and methods. This robust method ensures target values won’t change throughout the shelf life of the control and eliminates the need to spend time and money performing value assignment in house.
Accuracy coupled with unrivalled traceability to International Reference Laboratories, provides a product of unsurpassed accuracy and reliability.
Randox is a leading provider of multi-analyte, third party controls designed to help today’s busy laboratory significantly reduce the number of individual controls required to cover their test menu. Uniquely comprising up to 100 analytes in a single control product costs, preparation time and storage space are dramatically reduced without sacrificing on quality.
The presence of analytes at key decision levels in all Acusera controls will not only ensure test system performance across the clinical range but will further aid consolidation and maximise laboratory efficiency by eliminating the need to purchase additional and often expensive low or high level controls.
Working stability and product shelf life are important considerations for any lab when choosing which internal quality control material is best suited to their needs. Labs often spend up to one month validating new material, a process which can be minimised by opting for a control with an extended shelf life. At Randox our lyophilised controls have a shelf life of up to four years and our liquid controls a shelf life of up to two years from the date of manufacture ensuring continuity of lot supply and ultimately reducing the need for expensive new lot validation studies.
Each of our third party controls will have its own reconstituted or open vial stability, some of the analytes will have limitations, however we pride ourselves on not misleading customers with false claims. The extended open vial and reconstituted stabilities will help laboratories to minimise waste and reduce costs.
Traceability refers to the property of a measured result or calibrator value to be related or traced back to a reference measurement procedure or reference material through a series of measurements with known uncertainties.
The European parliament and council directive 98/79 EC require values assigned to both calibrators and control materials on in vitro diagnostic medical devices to be traceable to a recognised reference material or reference measurement procedure of higher order, e.g. SI units.
Guidelines have been set for diagnostic manufacturers to follow when assigning calibrator values and establishing traceability. These guidelines were set by the European standards EN/ISO 17511 and also EN/ISO 18153. The Randox traceability pathway has been established with reference to standards ISO 17511 and ISO 18153. The pathway has been followed to establish traceability for Randox calibrators allowing all patient results to be traced right back to the source.