search.noResults

search.searching

note.createNoteMessage

search.noResults

search.searching

orderForm.title

orderForm.productCode
orderForm.description
orderForm.quantity
orderForm.itemPrice
orderForm.price
orderForm.totalPrice
orderForm.deliveryDetails.billingAddress
orderForm.deliveryDetails.deliveryAddress
orderForm.noItems
EXTERNAL QUALITY ASSESSMENT nBiomedical scientist 1 nTrainee biomedical scientist nClinical scientist


nBiomedical scientist 4 nBiomedical scientist 3


nQuality manager nTraining officer nBiomedical scientist 2


3% 10% 3% 7% 3% 3% 38% 33%


material, quality of facilities and organisation, and value for money. Similarly, the content and delivery of the individual cases was rated by 94–100% of participants as ‘excellent’ or ‘good’. Comments particularly emphasised that delegates liked the interactive nature of the sessions – both working through the cases and the discussion afterwards – and real-world applicability of the problems. In the most recent survey, 100% of delegates would recommend the UK NEQAS IIA masterclass to a colleague. Some participants have said that it is


Typical breakdown of delegate attendance at UK NEQAS IIA EQA one-day masterclass events.


different assay problems and to show which sources of information are the most useful in troubleshooting. For some problems the internal QC chart is the most valuable. Here, questions that arise in reviewing QC include: What is the QC material and how stable is it? Are the concentrations used appropriate in terms of clinical decision thresholds? What is acceptable QC performance? How are the mean and standard deviation (SD) values on the chart assigned? What action should be (and actually is) taken if QC performance is poor? How are QC values re-assigned after recalibration or lot changes in reagent or QC material? For other cases the key problem is


calibration and how this is addressed to ensure traceability to an international standard. If there is no international reference preparation, what are the alternatives? Other problems relate to specificity: does it matter if an assay measures fragments of the analyte as well as the intact molecule, or if it is affected by different proportions of protein-bound and free analyte? Tests may be used for different purposes,


such as screening, diagnosis, prognosis, risk assessment and monitoring. The performance characteristics required will vary according to which of these is the purpose of the test. As an example, EQA shows a tumour marker giving a result twice as high in the assay from Manufacturer A than from Manufacturer B. Tumour markers in general are not used for screening or diagnosis, but are helpful for monitoring patients following treatment in order to confirm response and to detect relapse before it is clinically apparent. As long as Manufacturer A’s assay is reproducible (good precision), the assay difference may not be a problem if the marker is used to monitor patients over time. However, it does become a problem if a patient, previously seen at another hospital with stable results using Manufacturer B’s assay, moves into your


THE BIOMEDICAL SCIENTIST MAY 2016


area and appears to have suffered a relapse. If there are only two main method groups for the tumour marker and no international standard, the all-laboratory trimmed mean (ALTM) is not informative as the distribution will be bimodal and the mean is meaningless. If Manufacturer B becomes more popular it will have a greater influence on the ALTM and appear to be more ‘correct’ without any change in the assay’s true performance. One of the cases has looked at the options


available where there is no EQA scheme for a particular analyte. This may be because the test is new, superseded, rarely required, technically difficult, or the analyte is unstable. There are a number of approaches that may be used to satisfy the United Kingdom Accreditation Service (UKAS) accreditation standard for laboratories (ISO 17043:2012), one of which is sample exchange with another laboratory, and UK NEQAS IIA has recently set up a system by which potential users can find partners with whom to exchange samples. This approach is inherently less satisfactory than EQA and raises questions about sample transport and stability, performance assessment, and what to do if results are not concordant.


Participant feedback Over the three masterclasses held to date (one in 2014 and two in 2015) there have been 155 attendees. Of these, 130 completed a feedback questionnaire (84% response rate). The grades of staff attending have broken down as follows: approximately 70% biomedical scientists 1 and 2, 10% clinical scientists, and the remaining 20% comprising higher-grade biomedical scientists, quality managers, training officers and trainees. The feedback has been overwhelmingly positive, with 92–100% responding as ‘agree’ or ‘strongly agree’ to statements regarding the meeting of expectations, relevance to educational needs, containing new ideas and


difficult to take back the information to disseminate in their base laboratory, and to some extent this is probably true. Unlike a lecture-based study day, the emphasis is on developing skills in problem-solving and critical analysis, rather than conveying hard factual information. Another observation made is that the nature of the cases is heavily weighted towards immunology and immunochemistry. This is largely due to the fact that the masterclass is designed to complement the UK NEQAS IIA EQA schemes, which, by definition, limits the range of tests. However, these still cover a significant range of qualitative, quantitative, manual and automated assays, and to a large extent the actual assay is not important.


The general principles involved should be applicable to troubleshooting any assay, and sometimes approaching an unfamiliar test with a fresh pair of eyes is more effective than making assumptions about why a familiar test is performing poorly. It is better to start from first principles and ask what might seem to be naïve questions. One of the most important of these is: what is the clinical relevance of the test, and how good does the performance actually have to be in order to be fit for purpose? Many tests are done simply because they have always been done, and they may no longer add any clinical value, because diagnostic and clinical practice has moved on. Poor EQA performance may prompt a discussion with local clinicians and a decision to drop the test altogether. Other participants have commented that


there is not a final definitive answer in all the cases. This again is a true reflection of real life. We may need further information over time to identify the problem fully or we may be able to identify the cause of the problem but have no way to put it right. The problem identified may be so serious that it needs to be escalated as a clinical incident, which might involve retesting patients and informing the Medicines and Healthcare products Regulatory Agency (MHRA) if a product is likely to be at fault. Hopefully, the masterclasses will allow


participants to see the bigger picture beyond just filling a form to keep the EQA provider off their backs!


Dr Paul Masters is consultant chemical pathologist in Chesterfield and Chair of UK NEQAS IIA Immunochemistry Steering Committee.


243


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60