- ABO Grouping
- D grouping
- Antibody detection
- Antibody identification
- Red cell phenotyping
Aims of and participation in the scheme
The aims of all UK NEQAS Schemes are primarily educational. Provision of identical samples to all participating laboratories allows inter-laboratory comparison and also identifies the overall level of performance within the UK. Corrective action taken as a result of unsatisfactory performance can lead to an improvement in proficiency within an individual laboratory. Learning from others through reports of exercises, leads to an improvement within the UK as a whole. By linking results with techniques and procedures, specific strengths and weaknesses can be identified, driving change. National guidelines are reinforced and the need for new guidelines identified.
EQA forms an essential part of quality assurance within a laboratory and provides evidence of individual laboratory performance. However, it gives only a snapshot of a laboratory’s performance at any given time and the information reported back is inevitably a retrospective view. It should be undertaken in addition to, not in place of, other quality assurance measures.
Unlike EQA results in many other disciplines, blood group serology results are not a matter of consensus, and target values are not assigned as the result of statistical analysis. The results are analysed on the basis of whether they agree with the ‘true’ result based on testing in-house and by the supplier of the material. EQA is primarily intended to identify problems with systems, techniques, processes and procedures, and although the technical and interpretative skills of the person performing the test inevitably influence the results submitted (at least where testing is manual or only partially automated), EQA does not replace the need for continued operator competency assessment.
Participation in an appropriate, accredited EQA Scheme is a requirement of accreditation to CPA (UK) Ltd and ISO15189 standards.
Blood Transfusion Laboratory Practice
Scope and frequency of tests offered
There are four major exercises per year, coded ‘R’, covering all routine aspects of blood group serology. In addition, a further six exercises are issued, coded ‘E’, covering antibody detection and identification only. UK participants are expected to participate in all ten exercises if they routinely undertake antibody screening and/or antibody identification. There are a few specialist departments that only undertake ABO/D typing, and these participate in only the four ‘R’ coded exercises. Non-UK participants may elect to participate in the four ‘R’ coded exercises only. Exercises are numbered sequentially from 1 to 10, prefixed with the last two digits of the year and E or R as appropriate, e.g. 14R1, 14E2, refer to the first two exercises in 2014.
Participants receive a schedule of the survey despatch dates at registration or annual re-registration. The schedule is also published on the website. Any significant changes to the schedule are highlighted on the website and participants informed by email. If you are in the UK and the exercise material has not been received within three days after the published distribution date, you should phone the Scheme for advice. Laboratories outside of the UK should contact the scheme if the exercise material has not been received within four days after the published distribution date, or within the delivery limits quoted by the courier.
Both options are performance monitored for participation and analytical performance, for all the parameters listed.
- Major ‘R’ coded exercises (four per annum) comprise:
- Three ‘patient’ whole blood samples* for ABO and D typing, and DAT if required.
- Three ‘patient’ plasma samples** for antibody screening, antibody identification and crossmatching.
- Three ‘donor’ red cell samples for crossmatching and red cell phenotyping.
Whole blood samples are unsuitable for antibody screening, identification, auto control crossmatching, or phenotyping, unless indicated otherwise in the instructions. For this reason, theoretical ‘patient’ phenotypes are provided on the instruction sheet, unless the exercise format states otherwise.
Plasma samples are assumed, for the purposes of the exercise, to be from the same ‘patient’ as the corresponding whole blood sample. However, these may not always match in every respect including ABO, and it is important that they are only used for the tests indicated in the instructions and on the sample labels. It also makes them unsuitable to use as an auto control.
- Antibody screen/identification ‘E’ coded exercises (six per annum) comprise:
- Four ‘patient’ plasma samples for antibody screening and antibody identification.
Limited demographic details may be included with the exercise, such as age and gender, in which case these should be taken into account for interpretation of blood grouping results, and for issue of red cells.
The Scheme is advised by a Steering Committee. The Committee comprises scientific and clinical members and the membership is ratified by the UK NEQAS Executive Committee. The Chairman is independent of UK NEQAS operational issues, and is currently Dr Peter Baker, Blood Transfusion Laboratory Manager, Royal Liverpool University Hospital, L7 8XP.
Scope and Tests Offered
There are four exercises per year for D typing. Exercises are given a 5-digit code derived from the last two digits of the year, followed by R, a single-digit number, and a B; e.g. 14R4B.
The participating organisation receives a schedule of the survey despatch dates at registration or annual re-registration. The schedule is also published on the UK NEQAS website. Any significant changes to the schedule are highlighted on the website and participants informed by email. If the exercise material has not been received within three days after the published distribution date, please phone the Scheme for advice.
New registrations and amendments to existing registrations
Once authorised by the POCT organisation, details of new registrations or amendments to the details of existing participants are forwarded to UK NEQAS using the standard form provided.
The form is returned to the organisation by UK NEQAS confirming that the request has been authorised and implemented, and in the case of new registrations the completed form includes the PRN and other login details required for result submission.
ABO Titration Scheme
Following an exploratory pilot exercise in 2009 which demonstrated wide variation in practice and results, the ABO titration pilot scheme was launched in 2010 and became a full UK NEQAS Scheme in April 2017. The main aim is to assess practice and improve standardisation in centres undertaking ABO titration to support ABO incompatible (ABOi) solid organ transplant, where titration results influence decisions regarding acceptance of patients to the ABOi transplant programme and suitability for transplant. The scheme distributes plasma representing patient samples for titration, and red cells to titrate against. A ‘Standard’ technique (using BioRad (DiaMed) gel technology) has been developed as a tool to investigate variation in results and to achieve standardisation across centres. Participants are asked to submit results for the ‘Standard’ technique alongside their in-house technique where possible.
- ABO titration
- Occasional A1 typing (not currently performance monitored)
Data entry / reporting
Data entry and reporting is via this website. Exercise reports include the participant’s own results and summary data for the exercise (medians and range by method and technology). An annual report will be issued with collated data and discussion of the results.
Scoring is applied to results obtained by the ‘Standard’ indirect antiglobulin (IAT) and ‘Standard’ direct agglutination at room temperature (DRT) techniques (and other techniques with >=20 participating laboratories). Results with a titration value greater than one doubling dilution from the median result for that technique are scored. Performance monitoring based on these scores and on return of results is undertaken for UK laboratories only.
Availability to new participants
The Scheme is open to laboratories worldwide supporting ABOi solid organ transplant programmes, and also to those performing ABO titration for other clinical reasons. New participants can register their interest by emailing the scheme at [email protected] An information pack including a registration form, schedule and fee sheet will be emailed back.
Red Cell Genotyping Pilot Scheme
The UK NEQAS red cell genotyping pilot scheme was launched in 2016, following a pre-pilot project in collaboration with ISBT in 2014/15, where one of the outcomes was recognition that EQA for ‘routine’ red cell genotyping would be useful. The 2016/17 UK NEQAS pilot comprises four exercises, with three distributed in 2016 (June, September, December) and the final distribution scheduled for March 2017. The scheme will continue as a pilot in 2017/18, with the same frequency of distribution as for 2016/17, with a view to becoming a full UK NEQAS EQA Scheme in 2018/19. Future development of the Scheme will be undertaken with help from our scientific advisory group (current membership can be viewed on https://www.ukneqasbtlp.org/redcellgenotypingsag).
Genotype and predicted phenotype for D, Cc, Ee, MN, Ss, Kk, Fya, Fyb, Fy, Jka, Jkb, Doa and Dob. Each exercise comprises two whole blood samples representing samples from haemoglobinopathy patients referred for genotyping to facilitate transfusion support, and instructions for testing and reporting.
Exercise packages are dispatched by first class post within the UK and by courier (DHL) to non-UK participants. On each distribution day, an email is sent confirming that the exercise has been dispatched and including a link to an on-line SurveyMonkey questionnaire for result entry.
The responses (genotype and predicted phenotype) are presented as tickbox selections, using ISBT terminology. There is an ‘other’ option, for use only if is not be possible to select an option in ISBT terminology that represents the result obtained. If the result would be reported to clinicians in different terminology, this can be specified in a supplementary question in each section. A link to a table with ISBT terminology for common alleles is provided. Assessment is by comparison of each participant’s result vs. the consensus result for each allele. In the event of there not being clear consensus on a result, this will be investigated before reporting, and participants’ results reviewed in light of any further information. No scoring or performance monitoring will be applied whilst the scheme remains in the pilot phase. Reports are issued by email and include assessment of individual results, an indication of overall results for the exercise and a discussion. During the pilot phase whilst there is no dedicated IT for analysis, it is anticipated that reporting will take between 6 and 10 weeks.
Availability to new participants
Participation from UK and non-UK laboratories undertaking red cell genotyping is welcomed. New participants can register their interest by emailing the scheme at [email protected] An information pack including a registration form, schedule and fee sheet will be emailed back.
You should have received an annual schedule at registration or re-registration. A schedule can also be found on the website: http:\www.ukneqasbtlp.org
If they haven’t arrived by three days after the published distribution date (4 days for non-UK participants), you should phone the Scheme for advice.
Results can still be analysed until the reports have been published on the web. However, a non-return report will be sent in the first instance and will be replaced by a late-return report a week later. Late results do attract 50 penalty points and the testing must have been performed on or before the closing date, as we cannot guarantee the integrity of the samples after the closing date. If in doubt, contact the Scheme.
Phone the Scheme on 01923 217933 to request a repeat sample. You will be asked for your PRN and the reason for your request.
You are supplied with a randomly generated password. Although you may change this on request, there are some restrictions, e.g. the password must be at least 7 characters long and contain a mixture of alpha and numeric characters.
Given that there is only one correct result for each test, we recommend that laboratories do not have two separate registrations. We recommend that you subject one analyser to EQA and use daily IQC to assure that both are giving the same results. Alternatively, where the two analysers employ different processes, the EQA exercises can be alternated between the two, or half the samples tested on the first analyser and the other half on the second. The same approach can be used for manual testing.
Error scores cumulate over three consecutive exercises and the histograms display penalty scores for both the current exercise (shown by the open circle) and cumulative performance (closed circle).
Your laboratory is not registered for phenotyping and you should contact the Scheme by email to request a change in registration.