United Kingdom Accreditation Service Research Articles

A retrospective study of cases of canine demodicosis submitted to a commercial diagnostic laboratory servicing the United Kingdom and Ireland (2017–2018) part 2; Aerobic culture and antimicrobial susceptibility results

Clinical diagnostic reports from 508 cases of canine demodicosis diagnosed either by histological or skin scraping analysis from a United Kingdom Accreditation Service (UKAS) accredited veterinary diagnostic laboratory servicing the United Kingdom (UK) and Ireland were evaluated. Of the 508 cases, 284 had skin swabs submitted for culture on the same day the skin biopsy and/or skin scraping were obtained. Dogs with juvenile-onset (JO) demodicosis represented 57.4% of these cases, whilst adult-onset (AO) cases comprised 42.6%. The data revealed that overgrowth of pathogenic bacteria was more common in AO demodicosis cases (75.2%) in comparison to the JO cases (57%). Adult-onset cases also had increased involvement of bacteria belonging to multiple genera and/or yeast (28.9%) in comparison to JO cases (18.4%). Pruritus was significantly associated with an overgrowth of Staphylococcus pseudintermedius (p < 0.001). Resistance to one or more antimicrobial classes was noted in S. pseudintermedius isolates from 56.3% of JO cases with 10.3% of these cases being classified as Multi-Drug Resistant (MDR). Similarly, 51.9% of S. pseudintermedius isolates from the AO cases were noted to be resistant to one or more antimicrobial class with 8.6% of these cases being considered MDR. Cephalosporins were the most frequently administered antimicrobial class noted in submission histories, followed by the penicillin and fluoroquinolone classes. Whilst our findings reveal a high prevalence of concurrent overgrowth of pathogenic bacteria warranting therapeutic intervention in canine demodicosis, the presence of resistance within isolates highlights the need for prudent selection and targeted use of antimicrobial therapy that encompass the key principles of antimicrobial stewardship.

Development of a Gas-Tight Syringe Headspace GC-FID Method for the Detection of Ethanol, and a Description of the Legal and Practical Framework for Its Analysis, in Samples of English and Welsh Motorists' Blood and Urine.

Ethanol is the most commonly used recreational drug worldwide. This study describes the development and validation of a headspace gas chromatography flame ionisation detection (HS-GC-FID) method using dual columns and detectors for simultaneous separation and quantitation. The use of a dual-column, dual-detector HS-GC-FID to quantitate ethanol is a common analytical technique in forensic toxicology; however, most analytical systems utilise pressure-balance injection rather than a simplified gas-tight syringe, as per this technique. This study is the first to develop and validate a technique that meets the specifications of the United Kingdom’s requirements for road traffic toxicology testing using a Shimadzu GC-2014 gas-tight syringe. The calibration ranged from 10 to 400 mg/100 mL, with a target minimum linearity of r2 > 0.999, using tertiary butanol as the internal standard marker. The method has an expanded uncertainty at 99.73% confidence of 3.64% at 80 mg/100 mL, which is the blood alcohol limit for drink driving in England and Wales. In addition, at 200 mg%—the limit at which a custodial sentence may be imposed on the defendant—the expanded uncertainty was 1.95%. For both the 80 mg% and 200 mg% concentrations, no bias was present in the analytical method. This method displays sufficient separation for other alcohols, such as methanol, isopropanol, acetaldehyde, and acetone. The validation of this technique complies with the recommended laboratory guidelines set out by United Kingdom and Ireland Association of Forensic Toxicologists (UKIAFT), the recently issued Laboratory 51 guidelines by the United Kingdom Accreditation Service (UKAS), and the criteria set out by the California Code of Regulations (CCR), 17 CCR § 1220.1.

Performance evaluation of a non-invasive one-step multiplex RT-qPCR assay for detection of SARS-CoV-2 direct from saliva

Polymerase chain reaction (PCR) has proven to be the gold-standard for SARS-CoV-2 detection in clinical settings. The most common approaches rely on nasopharyngeal specimens obtained from swabs, followed by RNA extraction, reverse transcription and quantitative PCR. Although swab-based PCR is sensitive, swabbing is invasive and unpleasant to administer, reducing patient compliance for regular testing and resulting in an increased risk of improper sampling. To overcome these obstacles, we developed a non-invasive one-step RT-qPCR assay performed directly on saliva specimens. The University of Nottingham Asymptomatic Testing Service protocol simplifies sample collection and bypasses the need for RNA extraction, or additives, thus helping to encourage more regular testing and reducing processing time and costs. We have evaluated the assay against the performance criteria specified by the UK regulatory bodies and attained accreditation (BS EN ISO/IEC 17,025:2017) for SARS-CoV-2 diagnostic testing by the United Kingdom Accreditation Service. We observed a sensitivity of 1 viral copy per microlitre of saliva, and demonstrated a concordance of > 99.4% between our results and those of other accredited testing facilities. We concluded that saliva is a stable medium that allows for a highly precise, repeatable, and robust testing method.

RBS as a new primary direct reference method for measuring quantity of material

The quantity of material in thin films can be measured reliably, non-destructively, and at an absolute traceable accuracy with a combined standard uncertainty of 1% by Rutherford backscattering spectrometry (RBS). We have demonstrated a measurement protocol for the determination of quantity of material by RBS that has been accredited at this accuracy to the ISO 17025 standard by the United Kingdom Accreditation Service (UKAS). The method is entirely traceable to SI units relying on no artefacts, and thus qualifies as a primary direct reference method as defined by the ISO Guide 35:1985 (paragraph 9.4.1).

2016 Laboratory guidelines for postvasectomy semen analysis: Association of Biomedical Andrologists, the British Andrology Society and the British Association of Urological Surgeons

Post-vasectomy semen analysis (PVSA) is the procedure used to establish whether sperm are present in the semen following a vasectomy. PVSA is presently carried out by a wide variety of...

Quality in clinical cytometry

To understand how we achieve quality within a clinical flow cytometry setting we need to appreciate the difference between Quality Control (QC) and Quality Assurance (QA). QC may be defined as a procedure or set of procedures intended to ensure that a manufactured product or performed service adheres to a defined set of quality criteria. In contrast QA is the planned and systematic activities implemented in a quality system so that quality requirements for a product or service will be fulfilled. In general, one can look at QA as the overall description and control of a process while QC plays a part in control of the process. When looking at QA we need to consider how we control the pre analytical, analytical and post analytical process. These processes need to be documented and training and competence evidenced. The pre analytical process includes defining the specimen type that is acceptable, how it will be transported, what identification is required and whether this is the correct test for the patient. The analytical process is the part of the process that most scientists are familiar with. We have to ensure that we conduct the test using the correct methodology using suitable equipment (validation) and the reagents are suitable for purpose (verification). As part of the evidence for validation it is normal to refer to reference methods, published guidelines, biological reference material, external and internal QC. The post analytical process, like in the pre analytical process, is where we again have to look at how the laboratory interfaces with it’s users. Consideration has to be given to who is competent to interpret reports and advise service users, how we are going to report laboratory results so that the user understands them and finds them an aid to diagnosis and treatment. The International Organization for Standardization has developed a set of standards for medical laboratories, ISO 15189:2012. In the United Kingdom these standards have been adopted to replace the Clinical Pathology Accreditation standards and are accredited by the United Kingdom Accreditation Service (UKAS). The ISO 15189:2012 standards require laboratories to pay more attention to traceability of methods through the use of reference material (WHO, NIBSC etc.), reference methods and calibration as well as the competence, qualification and training of laboratory staff, how this is assessed and reviewed. Through adoption of these processes clinical flow cytometry laboratories can demonstrate robust analysis to support clinical diagnosis and are equipped to deal with the changing environment of clinical flow cytometry.

Development of new and accurate measurement devices (TruSlice and TruSlice Digital) for use in histological dissection: an attempt to improve specimen dissection precision

ABSTRACTHistological dissection of human tissue has relied on conventional procedures, which have largely remained unchanged for decades. Practices to determine measurement parameters employed in these procedures have largely relied on the use of rulers and weighing scales. It is well documented in the scientific literature that both fixation and processing of tissue can significantly affect the viability of the of tissue sections both for tinctorial and immunocytochemical investigations. Both of these factors can be compounded in their negative effects by inappropriate sampling of tissue at histological cut up. There are five key factors to ensure good surgical grossing technique, flat uniformly perpendicular specimen cutting face, appropriate immobilisation of the tissue specimen during grossing, good visualisation of the cutting tissue face, sharp cutting knives and the grossing knife action. Meeting these factors implies the devices are fit for purpose. Here we describe an innovative approach to designing cut up devices to improve accuracy and precision, which take these five key requirements into consideration. The devices showed accuracy and precision, enabling tissue slices to be produced in a uniformly perpendicular fashion to within 2 mm in thickness and to enable consistency and reproducibility of performance across a series of tissue types. The application of a digital rule on one of these devices ensures accuracy and also enables quality control issues to be clearly assessed. As cellular pathology laboratories conform to ever increasing standards of compliance and performance in practice, the advent of assured precision and accuracy at cut up is awaited. Recommendations from accreditation bodies such as the United Kingdom Accreditation Service (UKAS) continue to push for improvements in this area of histological investigation. These newly designed devices may give the answers to these requirements and provide the impetus for a new generation of innovative equipment for histological dissection.

국내석면조사기관의 질적 수준 평가를 위한 현황조사

Objectives: This study identified the general characteristics of asbestos inspection/analysis laboratories in Korea and confirmed the actual situations in terms of technical aspects from these characteristics. In addition, given the background of the current problem, it offers preliminary data for determining future plans for improvement. Methods: A questionnaire was developed and distributed to the asbestos inspection/analysis laboratories that used the ISO/IEC 17025 for asbestos sampling and testing by UKAS(United Kingdom Accreditation Service) and the Korea Laboratory Accreditation Scheme(KOLAS). A total of 202 institutions in Korea were selected for the study and 145(71.8%) questionnaires were returned. Results: The number of personnel of the surveyed institutions averaged <TEX>$4.2{\pm}2$</TEX> and 79.3% operated with less than five persons. In terms of education, the capital and other densely populated areas showed a high level of education(p<0.05). The level of education and facilities were determined by the magnitude of the institution(p<0.05). Institutions managed by highly educated directors were well-stocked with education and facilities(p<0.05). Institutions which had directors with considerable experiences received high scores overall and in particular higher scores in terms of education and facilities(p<0.05). At the level of the bottom five percent, the factor of education was 40.4% while the factor of measurement 49%, the factor of analysis 59%, the factor of facilities 61%, and the factor of survey 81%, respectively. Conclusions: To improve the quality of the institutions, in the short term, the problems identified in this study can be used to revise the related regulations. In the long term, a grading system of survey institutions needs to be established through the introduction of an accreditation system. However, the ongoing support of a government agency is required, including holding seminars and open education, suggesting guidelines for operation of asbestos inspection/analysis labs, and other means.

How strict should specimen acceptance or rejection criteria be for diagnostic semen analysis? An opinion

Medical laboratory accreditation (previously by Clinical Pathology Accreditation UK Ltd and now by the United Kingdom Accreditation Service) has been integral to improving standards and service quality in the UK. With the recent introduction of the ISO15189 standard, all laboratories offering a clinical diagnostic service are required to demonstrate further improvement, with more emphasis on validation and assessment of the uncertainty levels associated with testing. This applies not only to ‘bench testing’, but also to the evidence-base for all pre-analytical and post-analytical procedures. To reduce the risk of external influences on andrology test results, semen sample rejection criteria were developed, including confirmation of patient identity, a strict time limit from sample production to testing, the use of toxicity-tested containers, a prescribed sexual abstinence and a need for complete sample collection. However, such criteria were originally developed by the World Health Organization in order to standardise analysis rather than reject testing outright, and should therefore be implemented with caution. Rejecting samples with normal semen parameters because they fail to meet some of the criteria as outlined above would be a waste of resources and adversely affect user (the person who requested or provided the sample) satisfaction. This document evaluates the evidence base underlying commonly used criteria for specimen rejection and suggests how they may be applied more pragmatically in order to improve efficiency and reduce the waste of resources.

Quality assurance in the nuclear sector

Abstract The nuclear sector in the UK operates under regulation requiring assurance that the quality of radioactive measurements is “fit for purpose”. Laboratories operate a quality system under ISO 17025:2005 which is monitored by the United Kingdom Accreditation Service. Few of the test methods used in UK laboratories are based on standard methods so non-standard procedures are validated through the use of certified reference materials, and continued quality assurance is provided through participation in proficiency testing and interlaboratory comparison exercises. The majority of organisations accredited for radioactivity measurements under ISO 17025:2005 in the UK are environmental monitoring laboratories routinely processing soils, vegetation, air filters and water samples. There are no certified reference materials available in the UK or elsewhere adequately supporting the work of these laboratories. The same is true for the nuclear decommissioning and waste management community that regularly analyses concrete, soil, brick, sludge and oils for activities at Low Level Waste and Intermediate Waste Levels. The nuclear sector has a number of issues regarding availability of isotopic tracers for analysis, supplies of material for nuclear medicine, proficiency testing exercises involving representative matrices and activity levels but the most pressing need is in the area of certified reference materials for validation of methods analysing alpha, beta, and gamma emitting radionuclides.

An audit improves the quality of water within the dental unit water lines of general dental practices across the East of England

To evaluate and improve upon the quality of water emanating from the dental unit waterlines (DUWLs) which supply irrigation for dental handpieces and triple spray syringes in general practice. A prospective clinical audit. Seventy-two general dental practices in the East of England. In 2006, 124 dentists initially registered to participate in the audit. By 2007, 72 had begun and by 2008, 68 had completed the project. This involved collecting samples of water discharged from the DUWLs in the dental practices both before the start and mid-way through a morning session. These were tested microbiologically at a United Kingdom Accreditation Service testing laboratory. Before the audit, 56% of the DUWLs were reportedly flushed through for 2 minutes at the start of the day, 29% were purged for 20 seconds in between each patient, 50% were treated with a wide range of different disinfectant solutions, 44% were drained down dry at the end of the day and 9% had no cross-infection control measures applied to them at all. In the audit, 100% used a disinfectant solution alone, predominantly either Alpron or Sterilox. The minimum audit standard set was for the water samples to meet the United States' Centers for Disease Control and Prevention (CDC) guideline on the quality of DUWL water, namely that the United States' Environmental Protection Agency (EPA) regulatory standards for drinking water be adopted, in that no more than 5% of water samples should be contaminated with total coliforms and that they should not have more than 500 colony forming units per ml (cfu/ml) of heterotrophic water bacteria. However, the participating dentists were encouraged to try and achieve the more stringent European Union (EU) standards for potable (drinking) water, namely for the water samples to have neither Escherichia coli nor any other faecal coliforms present and for the aerobic colony count to be less than 100 cfu/ml at 22°C after 72 hours of culturing. In the pre-audit survey, none of the 72 DUWL water samples were contaminated with E. coli but in five of them (7%) coliforms were recovered. Only 25% reached the EU potable water standard, of which 11% had zero planktonic bacterial contamination. Three percent were above the EU standard but below the CDC guideline/EPA regulatory drinking water standard, while alarmingly, 72% of them failed to reach this minimum audit standard altogether. However, after the application of a suitable disinfectant for at least a month, the audit revealed that E. coli still remained absent in the water samples taken from the 68 DUWLs that completed the project and in only one (1.5%) were coliforms recovered. Remarkably, nearly 81% reached the EU potable water standard, of which 54% had zero planktonic bacterial contamination, with nearly an additional 6% reaching the American CDC/EPA standard and with only 13% failing outright. Clinical audit using appropriate DUWL disinfectants can result in the improvement of the quality of water that is discharged through DUWLs, thereby minimising both the risk of cross-infection to vulnerable patients as well as to dental staff chronically exposed to contaminated aerosols.

Validation of the Lloyds Pharmacy BP11 oscillometric blood pressure monitor according to the International Protocol of the European Society of Hypertension

The BP11 is currently one of the lowest-cost blood pressure (BP) monitors available in the UK and has sold approximately 1.5 million units since its launch in 2006. As access to home-use BP monitoring increases, it is important that such devices are validated so that consumers and clinicians can be confident of their accuracy. The device was validated using the European Society of Hypertension International Protocol. Data collection and analysis were carried out under the laboratory standard ISO17025. Adherence to the standard and protocol was audited on-site by the United Kingdom Accreditation Service. Nine sequential same-arm measurements were taken alternating between trained observers and the test device. Minor variations from the protocol are reported. The device passed both phases of the European Society of Hypertension International Protocol. The mean (standard deviation) of the difference between the observers and the device measurements was -1.2 (6.4) mmHg for systolic and 2.1 (6.8) mmHg for diastolic pressures, respectively. The BP11 BP monitor can be recommended for home and professional use in an adult population.

Population reference intervals for minimal erythemal doses in monochromator phototesting

Monochromator phototesting, to measure the minimal erythemal dose (MED), is useful in investigating patients with abnormal photosensitivity at different wavelengths. It relies on access to reliable, up-to-date data on the MED in normal individuals. The purpose of this study was to determine MED in normal subjects at different wavebands and compare these with historical controls. The study group consisted of 415 normal individuals (349 males) of skin types I-III living in Scotland. Age range was 18-83 years (median 31 years). Phototesting was performed using a monochromator at prescribed wavelengths from 295 to 430 nm. All calibrations were traceable to the National Physical Laboratory. Quality systems were maintained to ISO 9001 and ISO 17025 international standards and ultraviolet (UV) measurements accredited by the United Kingdom Accreditation Service (UKAS). The 95% reference interval (99% confidence interval for this) ranged from 6.8 to 27 mJ/cm(2) at 295 nm to >82,000 mJ/cm(2) at 430 nm. Results of the current investigation are broadly in agreement with values published 25 years ago by this centre. This validates the phototesting process based on the use of monochromators with attention to careful control of conditions during UV exposure and MED reading, supported by dosimetric calibration.

Accreditation to ISO 17025:2005 for the Radioactivity Metrology Group of the UK’s National Physical Laboratory

In the mid 1990s, the National Physical Laboratory (NPL) took the decision to seek external accreditation to the then UK national accreditation standard (M10, M10 supplement and M11) through the NPL’s National Measurement Accreditation Service (NAMAS). This paper details the reasoning behind that initial decision and, in particular, how this impinged on the day-to-day activities of the NPL’s Radioactivity Metrology Group (RMG). In the intervening decade, the accreditation standard has changed considerably; accreditation is now to the international standards ISO 9001:2000 (Quality Management Systems: Requirements) and ISO 17025:2005 (General Requirements for the Competence of Testing and Calibration Laboratories); accreditation is now carried out by a wholly separate successor organization to NAMAS, the United Kingdom Accreditation Service (UKAS). To meet the new accreditation requirements the RMG: realigned it’s scope of work; streamlined and consolidated written procedures, references and appendices; centralized the collection of written procedures, and clarified the document identification system. Future developments will include efforts for RMG accreditation for conducting proficiency tests and providing reference materials.

An audit improves the quality of water within the dental unit water lines of three separate facilities of a United Kingdom NHS Trust

To improve the quality of water emanating from dental unit waterlines (DUWLs). A prospective clinical audit. Three geographically separate district dental facilities of a United Kingdom NHS Trust, involving two community clinics and one hospital orthodontic department, which were evaluated between 2002 and 2004. Samples of water discharged from the DUWLs were collected prior to the start and midway through a morning session. These were tested microbiologically at a United Kingdom Accreditation Service testing laboratory within six hours of sampling. One of the clinics followed the contemporaneous BDA advice of flushing water through its DUWLs while the other two clinics used separate intermittent disinfection purging regimes instead. One of them used a two stage protocol of Ethylene Diamine Tetra-Acetic acid followed by hydrogen peroxide, while the other used Bio 2000 as a single agent, which was subsequently superseded by the continuous use of super-oxidised water (Sterilox). To assess whether the samples either met the American Dental Association's guideline on the quality of DUWL water, or the more stringent European Union standards for potable (drinking) water. The two units which used a disinfection regime both complied with the ADA guideline and the EU potable water standard. However, the unit which only flushed through its DUWLs without using a disinfectant failed to comply with either of them. After all three dental facilities subsequently standardised their DUWL disinfection regimes by using Bio 2000, the colony counts from all of the water samples thereafter remained well below the EU recommended level. The unit which progressed to using Sterilox as a continuous disinfectant achieved and maintained zero readings from its water samples. Clinical audit can result in the improvement of the quality of water that is discharged through DUWLs, thereby minimising both the risk of cross infection to vulnerable patients, as well as to dental staff chronically exposed to contaminated aerosols.

Briefing: UKAS accreditation—building better standards

In today's risk-averse climate it is increasingly important for civil engineers to demonstrate that they are achieving high standards at all times. Using a United Kingdom Accreditation Service (UKAS)-accredited evaluation service is the answer, says Graham Talbot of UKAS.

ISO 17025 application within racing chemistry: a case study

The upgrading of the traditional laboratory standard for analytical chemistry from a combination of ISO/IEC Guide 25 and EN45001 to ISO17025 has generated much discussion across the doping control sector for animal sports. This paper will outline an approach which originates within the spirit of the new standard, but which is then extended to a pragmatic implementation—which has led to full accreditation through the United Kingdom Accreditation Service (UKAS). A number of problem areas are highlighted and solutions proposed. Affected laboratories are distributed relatively sparsely around the world, and developments that occur internationally will undoubtedly have an impact upon the evolution of accreditation standards. It is, therefore, imperative that effective communication takes place to disseminate developments, and this paper is intended to prompt such discussion.

A new UKAS Accredited Calibration System for Ultraviolet Radiometers

A system has been designed to provide traceable calibration of ultraviolet (UV) radiometers used with broadband and extended sources of the type commonly employed in clinical phototherapy and photobiology research. Traceability requires both an unbroken chain of steps to the primary standard held by a national laboratory and the checking of those steps by an accreditation body. The system described is traceable to the cryogenic radiometer at the National Physical laboratory (NPL) and is accredited by the United Kingdom Accreditation Service (UKAS). The best expanded uncertainty that can be obtained for single wavelength irradiance responsivities is 7% (at 95% confidence) in the wavelength range 250-400 nm. The measured meter characteristics are used along with tabulated data on the spectral properties of the source and, if required, the action spectrum of the radiation to calculate an appropriate calibration for the meter.

Accreditation in the United Kingdom: responding to needs or 'changing the goalposts'?

The requirements for establishing the competence of organisations involved in testing, calibration, certification and inspection, and the criteria for their assessment and accreditation are specified in international guides and European standards. As these guides and standards are intended for use by a range of organisations and accreditation bodies, operating in different disciplines, they are written in general terms in order to be widely applicable. It follows that some interpretation of the requirements is needed in order to address the different ways in which both organisations and accreditation bodies operate. This may be seen by accredited organisations as providing an opportunity for accreditation bodies to 'change the goalposts'; the needs of these organisations and of their clients must be accommodated as far as possible, without diminishing the value of, or undermining confidence in, accreditation. The United Kingdom Accreditation Service has been listening to its customers, reviewing its activities and is offering a more flexible pragmatic approach to assessment and accreditation; some of the new developments are described.

A review of intercomparison exercises run by NPL from 1989–1997

The National Physical Laboratory is the national standards laboratory of the UK and is charged with maintaining primary measurement standards in the UK. These include standards in the field of ionising radiation and, in common with other National Standards Laboratories, NPL develops and maintains absolute standards of radioactivity. These are used to calibrate secondary standard instruments and also to prepare traceable standards of radioactivity at levels appropriate to the user community. Over the past eight years NPL has run a series of six environmental radioactivity measurement intercomparisons, aimed at evaluating the capabilities of laboratories measuring environmental radioactivity in the UK. This paper reviews the general progress made over the years by the participating laboratories with reference to those laboratories who are accredited by the United Kingdom Accreditation Service (UKAS). The first exercises made clear that (1) there was no account taken of cascade summing effects in γ-ray spectrometry measurements by many laboratories, (2) the calibration standards used, in some cases, were completely inappropriate for the work being undertaken, and (3) the nuclear decay data utilised by many laboratories (and in some cases, supplied by reputable manufactures) were either of an old vintage or incorrect. Over the years, the situation has changed somewhat in that participants are more aware of the pitfalls of measuring radioactivity. Finally, the effect that this has had on NPL's activities in the area of radionuclide metrology will also be described.