Governance, quality assurance and accreditation


1. Governance

The NHS Population Screening Explained sets out the general principles of screening.

The UK National Selection Committee (United Kingdom NSC) makes recommendations on the filtering policy.

The NHS England and Improvement (NHSEI) is responsible for the commissioning and operational implementation of national screening programs. The Office for Health Promotion (OHP), part of the Ministry of Health and Social Affairs (DHSC), supports the development of a screening policy based on United Kingdom NSC recommendations.

Commissioners and providers should refer to Sickle Cell Disease and Thalassemia (TBS) specification of the screening pathway requirements which provides an overview of the TBS screening by describing what needs to happen at each step.

2. Accreditation

Laboratories offering screening, including those performing DNA and / or PND confirmations for NHS sickle cell anemia and thalassemia (TBS) The screening program should:

The UK Accreditation Service (UKAS) reviews ISO 15189: 2012 and filtering requirements on behalf of the Filtering Quality Assurance Service (SQAS) and the NHS TBS Screening program.

3. Take a step back with particular reference to HbA2

A retrospective is a review of control records to identify those injured or at risk of harm as a result of a control security incident or serious incident. Retrospective analyzes or case reviews may also be done as part of fact finding to establish whether there has been a tracing incident. Backtracking can lead to a patient notification or reminder exercise.

If your external quality control shows HbA2 is not consensual, so a retrospection exercise should be considered. HbA2 values ​​below consensus are of particular concern because in this situation, thal thalassemia carriers may have been omitted.

The following steps are a guide to performing a retrospection exercise. Although not mathematically exact, the given calculation is suitable for this purpose. It should be noted that each situation is unique and you may wish to seek advice from your external quality control provider and the national NHS. TBS Screening program.

If a hindsight exercise is required, report it as a suspected security incident in accordance with Security Incident Management in NHS Screening Programs.

This is to inform regional authorities SQAS and the host organization responsible for the laboratory, in addition to the clinical teams concerned (including midwives).

The responsible organization will have to decide whether the duty of franchise applies.

3.1 Method

  1. Identify when the latest results were consistent with consensus.

  2. Going back should look at patient results from that point on until the results are consensus again. If it is not yet proven that there is consensus on the results, the actions described should continue prospectively.

  3. All patient results should be reviewed. However, the following formula will help identify patients requiring a more rigorous examination and possible recall:

Discrepancy value = HbA consensus2 less HbA2 obtained by your laboratory

Patients requiring careful examination = HbA2 share value (3.5%) minus your calculated deviation value

For example, if consensus = 3.6% and obtained = 3.2%, then the value of the deviation would be 3.6 minus 3.2 = 0.4%. In this scenario, all patients with HbA2 greater than or equal to 3.1% from when the last results were in the consensus should be carefully considered.

  1. Patients with HbA2 greater than the value identified using the above formula and with an MCH less than 27 pg not already identified as a carrier of thalassemia, must be recalled and retested.

  2. Patients with MCH greater than 27 pg and with HbA2 which would have been greater than 4.0% when the discrepancy value identified using the above formula is added to the initial result obtained must be recalled and retested.

  3. All other patients do not need to be recalled or retested.

4. Guidelines for the Analysis of Liquid Capillary Blood Samples

This service should be viewed as a special ‘on demand’ service to relieve parental anxiety and not as a safety solution or substitute for newborn bloodstains (NBS) screening program, or faster access to clinical care. If local arrangements can be implemented to achieve accelerated results from the routine NBS screening program, this approach should be encouraged. Laboratories that perform second-line testing for the NHS NBS The screening program would already meet most of these criteria.

Laboratory tests may be ordered on newborns for clinical reasons, but these guidelines were developed specifically for babies born to biological parents known to be at high risk. To be a high risk “1 in 4” pregnancy, the results of hemoglobinopathy must be known on both birth parents. Samples taken for other clinical diagnostic purposes do not fall within these guidelines, although the applicant may want to ensure that the laboratory has sufficient skill and expertise to analyze neonatal samples.

  1. The analytical technique for the initial capillary sample test and the second-line test should be appropriate for neonatal samples. Some analytical protocols and instruments are designed for testing the blood of adults and are not optimal for newborns.

  2. The laboratory must participate in appropriate external quality assurance (CEQ) which evaluates the analysis and interpretation of the results of newborn samples. British NEQAS provides quality control specimens appropriate for this job.

  3. Samples should be transported to the analytical laboratory reliably and quickly, using courier service if the sample needs to be returned, rather than risking delays by using the postal service.

  4. The results of both biological parents should be reviewed before reporting the result of the liquid capillary sample. As this is a service for pregnancies known to have a significant hemoglobinopathy risk of 1 in 4, the applicant should record the results of both birth parents on the application form.

  5. The liquid sample analysis laboratory is responsible for informing the newborn screening laboratory of the result. There must be documented local systems in place for this process. Any discrepancy between the 2 results should be promptly investigated locally by both laboratories and reported to the NHS TBS Screening program and regional team in the week following the detection of the deviation.

  6. Laboratories offering this service should collect data for audit purposes on the number of samples tested, turnaround times, and consistency with newborn screening results.

  7. If the results of the liquid capillary sample and the NHS NBS Screening program are in agreement with each other, so another confirmatory sample is not necessary.

  8. The laboratory should have standard operating procedures (POS) for analytical methods and processes for prompt local notification to relevant healthcare professionals for the hair sample result. The POS should include top-level verification of analytical results prior to reporting and follow-up of NBS screening result.

  9. A mother and baby ready to be sent home should not be hospitalized while awaiting the results of these tests.

  10. The laboratory must be accredited according to the NHS TBS Screening program requirements.

5. Screening assistance service

Laboratories may have questions about screening policy or the interpretation of results that are not easily answered by referring to this manual or manuals. Oxford University Hospitals NHS Trust provides laboratory testing support services through designated hotlines and secure messaging.

The National TBS screening program commissions this service, which supports requests for prenatal and newborn screening.

Telephone: 01865 572 769

Email: [email protected]

6. Helpful organizations and sites

For more information see:


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