External Quality Assurance Program Research Articles

Impact of External Quality Assurance on the Quality of Xpert MTB/RIF Testing in Viet Nam.

Following the endorsement of the Xpert MTB/RIF assay (Cepheid, Sunnyvale, CA, USA) by the World Health Organization (WHO) in 2010, Viet Nam's National Tuberculosis Control Program (NTP) began using GeneXpert instruments in NTP laboratories. In 2013, Viet Nam's NTP implemented an Xpert MTB/RIF external quality assurance (EQA) program in collaboration with the U.S. Centers for Disease Control and Prevention (CDC) and the Foundation for Innovative New Diagnostics (FIND). Proficiency-testing (PT) panels comprising five dried tube specimens (DTS) were sent to participating sites approximately twice a year from October 2013 to July 2016. The number of enrolled laboratories increased from 22 to 39 during the study period. Testing accuracy was assessed by comparing reported and expected results; percentage scores were assigned; and feedback reports were provided to sites. On-site evaluation (OSE) was conducted for underperforming laboratories. The results from the first five rounds demonstrate the positive impact of PT and targeted OSE visits on testing quality. On average, for every additional round of feedback, the odds of achieving PT scores of ≥80% increased 2.04-fold (95% confidence interval, 1.39- to 3.00-fold). Future work will include scaling up PT to all sites and maintaining the performance of participating laboratories while developing local panel production capacity.

RCPAQAP pilot program for Strongyloides detection

Background: Strongyloidiasis is an infectious disease caused by the parasitic roundworm Strongyloides stercoralis. Strongyloidiasis is endemic in tropical and subtropical regions and has been shown to have high prevalence in some remote communities in Australia.1,2 In immunocompromised individuals, Strongyloides infection can be fatal. In 2018, RCPAQAP Serology issued a Strongyloides Pilot Program to assess the suitability of introducing an external quality assurance (EQA) program.

Introduction of a body fluids external quality assurance program

Introduction of a body fluids external quality assurance program

Quality Assurance In The Medical Microbiology Laboratory

Abstract In each laboratory, a quality assurance program should be developed in order to obtain reliable results and to fulfil the requirements of quality standards in the field of microbiological laboratory tests. Microbiological diagnostics makes it possible to determine the etiological agent of infection and allow the selection of an appropriate therapy. The quality of test results are affected by pre-laboratory, laboratory and post-laboratory steps, which should be checked regularly. Constant internal quality control of performance in the laboratory and participation in external quality control programmes may ensure the quality of results. Internal quality control of the tests at all stages of routine microbiological diagnostics in the laboratory facilitates constant monitoring of the quality of results. Participation in interlaboratory external quality control programmes permits the quality of performance of tests routinely used in a laboratory to be assessed. 1. Introduction. 2. Quality assurance programme. 2.1. Factors affecting quality. 3. Internal quality control. 3.1. Quality control of identification tests. 3.2. Internal quality control of antimicrobial susceptibility testing and detecting resistance mechanisms. 3.3. Internal quality control of automated systems for identification and susceptibility testing. 4. External quality control. 4.1. External quality assurance programme participation rules. 5. Summary

LAMP: A CDC Program to Ensure the Quality of Blood-Lead Laboratory Measurements.

The Lead and Multielement Proficiency (LAMP) program is an external quality assurance program promoting high-quality blood-lead measurements. To investigate the ability of US laboratories, participating in the Centers for Disease Control and Prevention (CDC) LAMP program to accurately measure blood-lead levels (BLL) 0.70 to 47.5 μg/dL using evaluation criteria of ±2 μg/dL or 10%, whichever is greater. The CDC distributes bovine blood specimens to participating laboratories 4 times per year. We evaluated participant performance over 5 challenges on samples with BLL between 0.70 and 47.5 μg/dL. The CDC sent 15 pooled samples (3 samples shipped in 5 rounds) to US laboratories. The LAMP laboratories used 3 primary technologies to analyze lead in blood: inductively coupled plasma mass spectrometry, graphite furnace atomic absorption spectroscopy, and LeadCare technologies based on anodic stripping voltammetry. Laboratories reported their BLL analytical results to the CDC. The LAMP uses these results to provide performance feedback to the laboratories. The CDC sent blood samples to approximately 50 US laboratories for lead analysis. Of the approximately 200 laboratories enrolled in LAMP, 38 to 46 US laboratories provided data used in this report (January 2017 to March 2018). Laboratory precision ranged from 0.26 μg/dL for inductively coupled plasma mass spectrometry to 1.50 μg/dL for LeadCare instruments. All participating US LAMP laboratories reported accurate BLL for 89% of challenge samples, using the ±2 μg/dL or 10% evaluation criteria. Laboratories participating in the CDC's LAMP program can accurately measure blood lead using the current Clinical Laboratory Improvement Amendments of 1988 guidance of ±4 μg/dL or ±10%, with a success rate of 96%. However, when we apply limits of ±2 μg/dL or ±10%, the success rate drops to 89%. When challenged with samples that have target values between 3 and 5 μg/dL, nearly 100% of reported results fall within ±4 μg/dL, while 5% of the results fall outside of the acceptability criteria used by the CDC's LAMP program. As public health focuses on lower blood lead levels, laboratories must evaluate their ability to successfully meet these analytical challenges surrounding successfully measuring blood lead. In addition proposed CLIA guidelines (±2 μg/dL or 10%) would be achievable performance by a majority of US laboratories participating in the LAMP program.

The Challenges of Implementing a PD-L1 Proficiency Testing Program in Australia

Background. One important initiative that commenced at the Royal College of Pathologists of Australasia Quality Assurance Program (RCPAQAP) in 2017 was the collaboration with United Kingdom National External Quality Assessment Scheme (UK NEQAS) Immunocytochemistry (ICC) and In-Situ Hybridization (ISH) for the challenging implementation of a PD-L1 immunohistochemistry (IHC) proficiency testing program for non-small cell lung carcinoma (NSCLC). A RCPAQAP participant survey in 2016 showed that only eight laboratories were performing PD-L1 testing. The aim of the collaboration was to increase the sample size of the pilot program to provide meaningful results that could be reported back to RCPAQAP participants with appropriate recommendations. Other challenges of assessment included standardising the clinical cut-offs for positivity for each commercial assay, interpretation of laboratory developed tests (LDTs), using appropriate tissue to cover the critical interpretation points for each assay, interchangeability of clones and interpretation proficiency testing. Methods. The use of a ‘Gold Standard’ for each commercial assay was used as a baseline to compare participant results and tumour proportion score bin categories were implemented to harmonise interpretation across clones. Conclusions. The findings of the pre-pilot test suggest that the use of a clinically validated PD-L1 IHC assay performs better during assessment than adopting a laboratory developed test (LDT). The assessment committee also concluded that tonsil showed a better dynamic range of positivity than placenta. It was acknowledged that participants are limited by the platforms they have available and so it was suggested that validating an optimal method against the clinical assay and continual verification of the test may produce the expected result. The next big challenge is to extend proficiency testing from technical to interpretation. This is being implemented globally via the International Quality Network for Pathology (IQNPath) with participation through local External Quality Assurance programs, including RCPAQAP.

Performance evaluation of the re-standardized Abbott Architect anti-HBs assay

BackgroundAs defined by World Health Organization (WHO), an antibody level of ≥ 10mIU/mL to hepatitis B virus confers protection. With the launching of Abbott anti-HBs assay re-standardized to the 2nd WHO International Reference Preparation, a positive bias in antibody level would be anticipated. Manufacturer provides limited data for samples around the immune cut-off which has potential implication on vaccine guidance. ObjectivesTo evaluate the performance of the re-standardized Abbott Architect anti-HBs assay and to determine the impact of the upward shift. Study designA total of 52 samples, including 12 external quality assurance programme samples and 40 clinical samples were tested with both the Abbott 1st WHO standardized and the 2nd WHO re-standardized assay and results compared. The 2nd WHO anti-HBs standard and Acometrix anti-HBs control were also included for comparison. ResultsVerification of the re-standardized assay with the 2nd WHO anti-HBs standard revealed positive bias with mean closer to target value. Overall, the positive bias introduced by the new assay will only affect interpretation of samples with anti-HBs levels > 5.00 to < 10.00 mIU/mL previously tested on the Abbott 1st WHO standardized anti-HBs assay. ConclusionsFinal interpretation of immune status to hepatitis B was not affected by the upward shift following introduction of the new Abbott anti-HBs assay except for previously negative samples with anti-HBs levels between >5.00 to <10.00 mIU/mL.

International external quality assurance of JAK2 V617F quantification

External quality assurance (EQA) programs are vital to ensure high quality and standardized results in molecular diagnostics. It is important that EQA for quantitative analysis takes into account the variation in methodology. Results cannot be expected to be more accurate than limits of the technology used, and it is essential to recognize factors causing substantial outlier results. The present study aimed to identify parameters of specific importance for JAK2 V617F quantification by quantitative PCR, using different starting materials, assays, and technical platforms. Sixteen samples were issued to participating laboratories in two EQA rounds. In the first round, 19 laboratories from 11 European countries analyzing JAK2 V617F as part of their routine diagnostics returned results from in-house assays. In the second round, 25 laboratories from 17 countries participated. Despite variations in starting material, assay set-up and instrumentation the laboratories were generally well aligned in the EQA program. However, EQA based on a single technology appears to be a valuable tool to achieve standardization of the quantification of JAK2 V617F allelic burden.

External quality assessment for HIV rapid tests: challenges and opportunities in Haiti

HIV rapid diagnostic tests (RDTs) are instrumental in scaling-up HIV testing services (HTS) in low-income and middle-income countries (LMICs). HIV misdiagnosis is a growing concern in the era of expanded...

Considerations on PCR-based methods for malaria diagnosis in China malaria diagnosis reference laboratory network.

Precise diagnosis is a key measurement for malaria control and elimination, traditional microscopy and rapid diagnostic tests cannot satisfy the requirements especially in the low transmission endemic areas or in the malaria elimination phase. Polymerase chain reaction (PCR) with high sensitivity and specificity can be considered as a diagnostic standard while no uniform PCR assay was established due to variations in their performance and lack of formal external quality assurance programs for validation for PCR assays in use. Here, 24 articles including 43 paired comparative evaluations limited to paired comparison of diagnostic performance between real-time PCR and conventional PCR to detect plasmodium in blood samples of human subjects from clinics or the field are systematically summarized. And according to the Landis and Koch classification, nineteen pairs showed almost perfect agreement, followed by 8 pairs of moderate agreement and 4 pairs of good agreement, while the kappa values of 12 pairs couldn't be examined. Moreover, the performance of 14 pairs were completely the same and 8 pairs had no differences, but 14 pairs were significant different including 8 pairs of real-time PCR with better performance than conventional PCR. Therefore, it is still an outstanding issue to choose PCR methods, and more work such as the standardization of materials and methods in use and their availability are needed to settle priority to better promote the role of malaria diagnosis reference laboratories.

Informatics External Quality Assurance (IEQA) Down Under: evaluation of a pilot implementation

External quality assurance (EQA) provides ongoing evaluation to verify that laboratory medicine results conform to quality standards expected for patient care. While attention has focused predominantly on test accuracy, the diagnostic phases, consisting of pre- and post-laboratory phases of testing, have thus far lagged in the development of an appropriate diagnostic-phase EQA program. One of the challenges faced by Australian EQA has been a lack of standardisation or “harmonisation” resulting from variations in reporting between different laboratory medicine providers. This may introduce interpretation errors and misunderstanding of results by clinicians, resulting in a threat to patient safety. While initiatives such as the Australian Pathology Information, Terminology and Units Standardisation (PITUS) program have produced Standards for Pathology Informatics in Australia (SPIA), conformity to these requires regular monitoring to maintain integrity of data between sending (laboratory medicine providers) and receiving (physicians, MyHealth Record, registries) organisations’ systems. The PITUS 16 Informatics EQA (IEQA) Project together with the Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) has created a system to perform quality assurance on the electronic laboratory message when the laboratory sends a result back to the EQA provider. The purpose of this study was to perform a small scale pilot implementation of an IEQA protocol, which was performed to test the suitability of the system to check compliance of existing Health Level-7 (HL7 v2.4) reporting standards localised and constrained by the RCPA SPIA. Here, we present key milestones from the implementation, including: (1) software development, (2) installation, and verification of the system and communication services, (3) implementation of the IEQA program and compliance testing of the received HL7 v2.4 report messages, (4) compilation of a draft Informatics Program Survey Report for each laboratory and (5) review consisting of presentation of a report showing the compliance checking tool to each participating laboratory.

Development of a pilot proficiency program for human papillomavirus DNA detection

Human papillomavirus (HPV) DNA testing has become routine in many diagnostic laboratories, particularly with changes from cervical cytology to HPV DNA as primary screening as of 1 December 2017 in Australia. External quality assurance (EQA) is essential for assessment of laboratory performance once HPV testing is implemented. The aim of this study was to develop a pilot program to evaluate and determine stability of material that could be utilised in an ongoing external quality assurance program (EQAP). Two sample types were evaluated: cells in PreservCyt solution (ThinPrep) from stored clinical specimens and HPV-seeded swabs. Two panels sent 5 months apart were distributed to 18 Australian and two New Zealand laboratories (participants) for testing by Hybrid Capture 2 (HC2) or alternative molecular methods. Participants were given 1 month to test specimens. Eight ThinPrep specimens in Panel 1 were reported correctly by 73% (11/15) of HC2 participants and 40% (2/5) of participants performing alternative methods. Of eight dry swab specimens, 58% (23/40) and 78% (25/32) were correctly identified by HC2 and alternative methods, respectively. Panel 2 included four ThinPrep and two swab specimens. ThinPrep specimens were reported correctly by 100% (60/60) of participants utilising HC2 and 95% (19/20) utilising alternative methods. Dry swab specimens were reported correctly by 89% (25/28) of participants utilising HC2 and 100% (10/10) of participants utilising alternative methods. These results indicate that both specimen types are suitable for utilisation in an EQAP and outline some issues of EQAP for ongoing assessment of HPV molecular methods in diagnostic molecular laboratories.

The stability of HIV-1 nucleic acid in whole blood and improved detection of HIV-1 in alternative specimen types when compared to Dried Blood Spot (DBS) specimens

BackgroundCommercially-available kits for HIV-1 detection include instructions for detecting HIV-1 in plasma and DBS, but don’t support other specimen types. ObjectivesShow quantitative stability of HIV-1 total nucleic acid (TNA) in blood and improved HIV-1 detection in alternative specimen types. Study designWhole blood and DBS specimens, tested as part of an external quality assurance program for qualitative HIV-1 detection, were used to evaluated error rates (false negative [FN], false positive [FP] and indeterminant [IND] results) across assays (internally developed [IH], Roche Amplicor [RA], and Roche TaqMan Qual [TQ]) and specimen types (frozen whole blood [BLD], DBS and cell pellets [PEL]). A modified Roche TaqMan HIV-1 assay was used to quantify HIV-1 TNA. ResultsSignificantly higher error rates were noted in DBS across all of the assays (4% vs. 0% for DBS and PEL, IH, p = 0.005; 4% vs. 0.1% for DBS and PEL, RA, p < 0.001; 10% vs. 1% for DBS and PEL or BLD, TQ, p < 0.001). HIV TNA concentration is stable in BLD (day 1 vs. day 10, p = 0.39) and higher than DBS (p < 0.001). ConclusionsTransporting refrigerated whole blood for centralized processing into alternative specimen types will improve the sensitivitiy of HIV-1 detection in samples with low virus loads.

Interlaboratory Evaluation of the U.S. Food and Drug Administration Escherichia coli Identification Microarray for Profiling Shiga Toxin–Producing Escherichia coli

The U.S. Food and Drug Administration Escherichia coli Identification (FDA-ECID) microarray provides rapid molecular characterization of E. coli. The effectiveness of the FDA-ECID for characterizing Shiga toxin-producing E. coli (STEC) was evaluated by three federal laboratories and one reference laboratory with a panel of 54 reference E. coli strains from the External Quality Assurance program. Strains were tested by FDA-ECID for molecular serotyping (O and H antigens), Shiga toxin subtyping, and the presence of the ehxA and eae genes for enterohemolysin and intimin, respectively. The FDA-ECID O typing was 96% reproducible among the four laboratories and 94% accurate compared with the reference External Quality Assurance data. Discrepancies were due to the absence of O41 target loci on the array and to two pairs of O types with identical target sequences. H typing was 96% reproducible and 100% accurate, with discrepancies due to two strains from one laboratory that were identified as mixed by FDA-ECID. Shiga toxin (Stx) type 1 subtyping was 100% reproducible and accurate, and Stx2 subtyping was 100% reproducible but only 64% accurate. FDA-ECID identified most Stx2 subtypes but had difficulty distinguishing among stx2a, stx2c, and stx2d genes because of close similarities of these sequences. FDA-ECID was 100% effective for detecting ehxA and eae and accurately subtyped the eae alleles. This interlaboratory study revealed that FDA-ECID for STEC characterization was highly reproducible for molecular serotyping, stx and eae subtyping, and ehxA detection. However, the array was less useful for distinguishing among the highly homologous O antigen genes and the stx2a, stx2c, and stx2d subtypes.

Review of diagnostic error in anatomical pathology and the role and value of second opinions in error prevention

AimsDiagnostic/interpretative accuracy can be challenging in anatomical pathology due to the subjective element of the diagnostic process. This can lead to false-negative or false-positive diagnoses of malignancy, variations in grading...

Factors which contributed for low quality sputum smears for the detection of acid fast bacilli (AFB) at selected health centers in Ethiopia: A quality control perspective.

ObjectivesQuality of tuberculosis (TB) microscopy diagnosis is not a guarantee despite implementation of External Quality Assurance (EQA) service in all laboratories of health facilities. Hence, we aimed at evaluating the technical quality and the findings of sputum smear microscopy for acid fast bacilli (AFB) at health centers in Hararge Zone, Oromia Region, Ethiopia.MethodsA cross-sectional study was carried out between July 8, 2014 and July 7, 2015.A pre-tested structured questionnaire was used to collect data. Lot Quality Assurance Sampling (LQAS) method was put into practice for collecting all necessary sample slides. Data were analyzed by using SPSS (Statistical Package for Social Sciences) version 20 software. P-value < 0.05 was considered as statistically significant.ResultsOf the total55 health center laboratories which had been assessed during the study period, 20 (36.4%) had major technical errors; 13 (23.6%) had 15 false negative results and 17 (30.9%) had 22 false positive results. Moreover, poor specimen quality, smear size, smear thickness, staining and evenness were indicated in 40 (72.7%), 39 (70.9%), 37 (67.3%), 27(49.1%) and 37 (67.3%) of the collected samples, respectively. False negative AFB findings were significantly associated with lack of Internal Quality Control (IQC) measures (AOR (Adjusted Odds Ratio): 2.90 (95% CI (Confidence Interval): 1.25,6.75) and poor staining procedures (AOR: 2.16(95% CI: 1.01, 5.11).ConclusionsThe qualities of AFB smear microscopy reading and smearing were low in most of the laboratories of the health centers. Therefore, it is essential to strength EQA program through building the capacity of laboratory professionals.

Commutability and traceability in EQA programs

ObjectivesThe concept of commutability of samples has focused laboratories on the importance of traceability. However, the critical role of External Quality Assurance (EQA) in achieving the primary role of traceability (i.e. facilitating comparable patient results in different laboratories) has largely been lost. The aim of this paper is to review the role of EQA in achieving traceable/commutable results. Design and methodsThe role of commutability and traceability in EQA and Internal Quality Control (IQC) are discussed. Examples of commutable EQA samples are given to highlight the problem of assuming EQA material does not behave like patient samples. ResultsWe provide the conventional traceability chain (top down) and the role of EQA in a “bottom up” model using conventional EQA samples. ConclusionsThe quest for commutable samples has compromised the value of EQA without an understanding that some EQA materials are commutable for some measurands.EQA plays a key role in performance improvement, but laboratories need to understand the importance of using a range of values appropriate to the assay to identify areas of quality need. Traceability and EQA using conventional samples are not mutually exclusive concepts.

Novel artificial stool material for external quality assurance (EQA) on a fecal immunochemical test for hemoglobin (FIT): The confirmed utility of stable hemoglobin and an internal standard material

The fecal immunochemical test for hemoglobin (FIT), which detects lower gastrointestinal bleeding, is widely accepted for population-based colorectal cancer (CRC) screening programs. However, the FIT screening process has not been standardized yet, and standardizing the pre-analytical phase and establishing an external quality assurance (EQA) program compliant with ISO requirements is urgently needed. Although there have been various attempts to establish EQA materials suitable for FIT, no materials have yet been reported to have sufficient uniformity and acceptable immunochemical stability of hemoglobin (Hb). The Health Care Technology Foundation (HECTEF; Tokyo Japan) is now developing a ready-to-use artificial stool containing Hb and an internal standard, glycerol. Accordingly, we verified the adaptability and efficacy of this material for the evaluation of the specimen collection phase of FIT. This material uniformly contained both Hb and glycerol. The glycerol allowed us to estimate the weight of the collected artificial stool and to correct the Hb concentration with the estimated weight. Furthermore, the stability of both Hb and glycerol were confirmed to be sufficient for an EQA material under appropriate storage, in-use, repeated freeze-thaw, and heated conditions. These in-house performance characteristics suggest that HECTEF artificial stool is acceptable as an EQA material for FIT.

Current state and recommendations for harmonization of serum/plasma 17-hydroxyprogesterone mass spectrometry methods

Abstract Background: Mass spectrometry (MS)-based 17-hydroxyprogesterone (17OHP) methods show considerable variation in results in external quality assurance (EQA) programs. An understanding of the current status of MS-based serum/plasma 17OHP quantification is important to facilitate harmonization. Methods: A 50-item e-survey related to (1) laboratory characteristics, (2) pre-analytical considerations and (3) analysis of 17OHP was developed and circulated to clinical MS laboratories via professional associations in Asia Pacific, Europe and North America. Results: Forty-four laboratories from 17 countries completed the survey. Sample preparation varied between laboratories with protein precipitation and liquid-liquid extraction being the most common processes. Analyte separation was most commonly achieved by liquid chromatography (LC) using a C18 column and mobile phases of water, methanol and formic acid. The ions selected for quantification were 331&gt;97 m/z or 331&gt;109 m/z. Alternative transition ions were used as qualifiers. Twenty-seven of 44 respondents reported preparing their calibrators in-house and variations in material purity and matrix were evident. Nine of 44 laboratories did not participate in an EQA program, and half did not know if their method separated out isobars. The reference intervals, and also their partitioning, reported by the laboratories were highly discrepant, in some cases, by multiple folds. Conclusions: Although MS-based methods are similar in many facets, they are highly disparate. Five recommendations have been developed as an outcome of this survey to support the continued improvement of analysis of serum/plasma 17OHP by MS.

Challenging assay robustness with RCPAQAP external quality assurance programs

Background: External quality assurance (EQA) programs commonly test for precision and accuracy of quantitative assays, but less frequently for common interferences that could potentially impact patient results. RCPA Quality Assurance Programs (RCPAQAP) in conjunction with the Australasian Association of Clinical Biochemists (AACB) now includes challenge samples in Chemical Pathology programs.