Test Points Research Articles

Utility of Central 10 Degrees Visual Field Test With Size V Stimulus in End-Stage Glaucoma.

In end-stage glaucoma, the central 10-degree visual field test with a size V stimulus provided useful information, including the number of points with detectable retinal sensitivity threshold values and retinal sensitivity threshold values. The purpose of this study was to evaluate the clinical utility of the central 10-degree visual field test with a size V stimulus in end-stage glaucoma. A total of 73 eyes with end-stage glaucoma (visual field limited to a radius of <10 degrees from fixation) were included. Central 10 degrees visual field tests were performed using both size III and V stimuli. Reliability indices, test duration, number of points with detectable retinal sensitivity threshold values, and retinal sensitivity threshold values at 4 central points, 4 quadrants, and 3 clusters (papillomacular area, superior half, and inferior half) were compared between the test results using size III and V stimuli. When the size V stimulus was used, the mean test duration increased from 7.8 to 13.3 minutes ( P < 0.001), the mean number of test points with detectable retinal sensitivity threshold values in total area increased from 19.0 to 37.3 ( P < 0.001), and the mean retinal sensitivity threshold values in total area increased from 3.9 to 9.3 dB ( P < 0.001) compared with the test results with the size III stimulus. Significant increase in the visual field parameters was found in all quadrants and clusters ( P < 0.001), and a greater increase was associated with better visual acuity and greater mean deviation of the visual field ( P < 0.05). The central 10-degree visual field test with a size V stimulus provided more information than the test with a size III stimulus in end-stage glaucoma.

Effects of the COVID-19 Pandemic on Legionella Water Management Program Performance across a United States Lodging Organization.

Legionella, the bacterium that causes Legionnaires' disease, can grow and spread in building water systems and devices. The COVID-19 pandemic impacted building water systems through reductions in water usage. Legionella growth risk factors can be mitigated through control measures, such as flushing, to address stagnation, as part of a water management program (WMP). A national lodging organization (NLO) provided WMP data, including Legionella environmental testing results for periods before and during the pandemic. The statistical analysis revealed an increased risk of water samples testing positive for Legionella during the pandemic, with the greatest increase in risk observed at the building's cold-water entry test point. Sample positivity did not vary by season, highlighting the importance of year-round Legionella control activities. The NLO's flushing requirements may have prevented an increased risk of Legionella growth during the pandemic. However, additional control measures may be needed for some facilities that experience Legionella detections. This analysis provides needed evidence for the use of flushing to mitigate the impacts of building water stagnation, as well as the value of routine Legionella testing for WMP validation. Furthermore, this report reinforces the idea that WMPs remain the optimal tool to reduce the risk of Legionella growth and spread in building water systems.

Numerical modelling and experimental testing of vibration-based debonding quantification on tile panels

Interfacial debonding is recognized as the most critical failure mechanism in adhesively bonded tiling systems which may cause potential falling of tile panels. Several techniques have been well developed in this field to assess the tiling systems in terms of the existence of debonding. However, limited research has been found to be capable of quantifying the debonding. In addition, previous studies typically employed a one-excitation, one-detection approach with a large amount of testing points, and often targeted large debonding sizes. This research aims to fill the gaps by investigating the vibration responses of tile panels and identifying appropriate approaches for debonding quantification. It introduces a more efficient standardised one-excitation, multiple-detection method, reducing testing points required and extending the capability to smaller debonding sizes. Numerical simulation and experimental studies were conducted, and responses were collected and analysed in the frequency domain. Both benchmark-based and benchmark-free approaches were proposed with relevant quantification indicators correlated to debonding size. It was found that the natural frequency and energy within the lower frequency band are effective indicators of the debonding size when a benchmark is available for comparison. In the absence of benchmark, the correlation coefficient between different quadrants of the tile panels is capable of quantifying the debonding size. Additionally, the quadrant where the defect is most likely located can also be identified.

Testability design of power distribution system considering noise immunity characteristics

MOSFET-based power electronics systems have high-reliability requirements, and a high-accuracy fault diagnosis method is necessary. However, imperfect conditions such as severe signal noise and poor consistency exist in actual products. Conventional fault diagnosis methods are difficult to identify faults accurately. This paper describes a simulation-based testability design method for batch products considering noise immunity. First, the components' soft and hard fault models are determined with failure mode and effect analysis (FMEA), and the circuit simulation model is constructed. Then, the fault injection simulation is performed to structure the dependency matrix. The test points scheme is selected and optimized by extracting noise immunity characteristics of different types of signals. Finally, a power distribution system is taken as a case study for the testability design method, and the effectiveness of the test points is evaluated through simulation and experiment verification.

Analytical Model Development for Rotors Hovering Above Heaving Surfaces

A potential flow model was developed for rotors hovering in-ground-effect above a heaving surface using a similar methodology to classical, analytical, static ground effect models. Experimental performance measurements for rotors hovering above a surface undergoing single degree-of-freedom heaving motion were used for model validation, and potential mission trends were generated for a representative naval helicopter. Unlike prior empirical models, the current model was able to capture the effect of rotor hub height as well as ground motion parameters. A new thrust ratio was proposed that compared the thrust produced in-ground-effect above a heaving surface to that produced above a static surface. Better agreement was found to occur at the higher collective pitch settings and hub heights, with the model predicting the classical thrust ratio within 5% of the measured value for approximately 75% of the test points. The thrust ratio relative to a static surface was found to produce better agreement, and approximately 80% of the experimental tests points were predicted within 5% of the measured value.

Advance on fiber optic‐based biosensors for precision medicine: From diagnosis to therapy

AbstractPrecision medicine that takes individual variability into account is a new way to minimize the individual variability for precise diagnosis and to establish the certain strategies of efficient therapy. Due to miniaturization sensing area, remoting detection, and flexible operation of light, fiber optics have been successfully used to develop in vitro, wearable, and implanted biosensors, exhibiting high potential in precision medicine from the diagnosis in vitro to therapy in vivo. When modified with the recognition element, the fiber optic‐based biosensor enables the point of care testing for the detection of disease biomarkers. Meanwhile, the fiber optics packaged in a needle/catheter also monitor the medical Internet of things for the continuous assessment of human health. Moreover, the light from the cladding or leaky mode in the fiber optics excites the strong photothermal effect for therapy. The fiber optic‐based biosensor addressed the drawbacks of plasmonic photothermal therapy that limited penetration depths and non‐selectivity therapy. When integrated with a photothermal agent, the fiber optic‐based biosensors provide in situ information for the diagnosis as well as specifically and efficiently kill the tumor cells in deep tissues. In this review, we summarized the advances of fiber optic‐based biosensors in the diagnosis in vitro and therapy in vivo. The challenges and prospection of the fiber optic‐based biosensor application in precision medicine were also explored in depth.

ERAS Cardiac Society turnkey order set for patient blood management: Proceedings from the AATS ERAS Conclave 2023

ObjectivesThere are multiple published guidelines on comprehensive patient blood management (PBM), centered on the 3 pillars of PBM: managing preoperative anemia, minimizing blood loss, and tolerating intraoperative/postoperative anemia. We sought to create an order set to facilitate widespread implementation of evidence-based PBM for cardiac surgery patients. MethodsSubject matter experts were consulted to translate existing guidelines and literature into a sample turnkey order set (TKO) for PBM. Orders derived from consistent class I, class IIA, or equivalent recommendations across referenced guidelines and consensus manuscripts appear in the TKO in bold type. Selected orders that were inconsistently class I or IIA, class IIB, or supported by published evidence are presented in italic type. ResultsPreoperatively, there are strong recommendations to screen and treat preoperative anemia with iron replacement and erythropoietin and to discontinue dual antiplatelet therapy if the patient can safely wait for surgery. Intraoperative orders outline the routine use of an antifibrinolytic agent, cell saver, point of care viscoelastic testing, and use of a standard transfusion algorithm. The order set also reflects strong recommendations intraoperatively and postoperatively for agreed-upon hemoglobin thresholds to consider transfusion of packed red blood cells. A hemoglobin threshold should be adopted according to local team consensus and should trigger a discussion regarding transfusion. ConclusionsThe benefit of a multidisciplinary PBM care pathway in cardiac surgery has been well established, yet implementation remains variable. Using recommendations from existing guidelines, we have created a TKO to facilitate the implementation of PBM.

High-sensitive detection and quantitation of thyroid-stimulating hormone (TSH) from capillary/fingerstick and venepuncture whole-blood using fluorescence-based rapid lateral flow immunoassay (LFIA)

BackgroundIn the last decade, point of care testing (POCT) such as lateral flow immunoassays (LFIA) were developed for rapid TSH measurement. Most of these TSH-LFIAs are designed for qualitative measurements (i.e., if TSH values > 5, or >15 IU/L) and as screening tests for primary hypothyroidism in children and adults. Serum or plasma, but not venepuncture whole-blood or fingerstick/capillary, are usually used to quantify TSH accurately. Studies on performance evaluation of TSH-LFIAs POCT using venepuncture or fingerstick whole-blood are limited. Additionally, limited studies evaluated the performance and validity of TSH-LFIAs POCT compared to valid and reliable reference methods. To our knowledge, this is the first study to evaluate three different blood withdrawal techniques for evaluating POCT of TSH. AimWe aim to evaluate the performance of a new fluorescence-based LFIA and its Finecare™ fluorescent reader for quantitative measurement of TSH from a fingerstick, venepuncture whole-blood, and serum. Methods102 fingerstick, venepuncture whole-blood, and serum samples (with normal and abnormal TSH values) were analyzed by Finecare™ Rapid Quantitative LFIA test and Roche cobas® e 601 as a reference test. ResultsUsing serum, when compared to cobas® e 601 reference method, Finecare™ showed high sensitivity [90.5 % (69.6–98.8)] and specificity [96.3 % (89.6–99.2)] for diagnosis of thyroid abnormalities (<0.35 or >4.5 mIU/L). The actual test values (mIU/L) of Finecare™ showed excellent agreement (Cohen's Kappa = 0.85) and strong correlation (r = 0.93, p < 0.0001) with cobas® e 601. Using venepuncture whole-blood samples, Finecare™ showed similar results to serum with high sensitivity [95.2 % (76.2–99.9)], specificity [97.5 % (91.4–99.7)], excellent agreement (Cohen's Kappa = 0.91), and very strong correlation (r = 0.95, p < 0.0001) with cobas® e 601. These results suggest that Finecare™ can be used for quantitative measurement of TSH using serum or venepuncture whole-blood. These key performance indicators were slightly decreased when fingerstick whole-blood samples were used: sensitivity [85.7 %(63.7–97)], specificity [90.0 %,(81.5–96)], good agreement (Cohen's Kappa = 0.7) and very strong correlation (r = 0.9, p < 0.0001) with cobas® e 601. A subgroup analysis of abnormal TSH samples revealed a strong and significant correlation between the reference, Finecare™ whole-blood (r = 0.692; p = 0.0015), and fingerstick test Finecare™ (r = 0.66; p = 0.0025). A very strong correlation was also observed between cobas® e 601 serum and Finecare™ serum (r = 0.88; p < 0.0001). Conclusion: In comparison to the reference assay, our study demonstrates that Finecare™ exhibits high sensitivity, specificity, agreement, and a strong correlation. These findings provide evidence that Finecare™ is a reliable, valid, and accurate point-of-care test for TSH screening and quantitative measurement, especially in non- or small laboratory settings.

Establishing proof of concept for utility of Trueprep®-extracted DNA in line-probe assay testing.

BACKGROUND AND OBJECTIVES: With an increased demand for rapid, diagnostic tools for TB and drug resistance detection, Truenat® MTB-RIF assay has proven to be a rapid point of care molecular test. The present study aimed to establish a proof of concept of using Trueprep-extracted DNA for line-probe assay (LPA) testing.METHODS: A total of 150 sputum samples (MTB-positive at Truenat sites) were divided into two aliquots. One aliquot was used for DNA extraction using the Trueprep device and MTB testing. The second aliquot of the sample was subjected to GenoLyse® DNA extraction. DNA from both the Trueprep and GenoLyse methods was subjected to first-line (FL) and second-line (SL) LPA testing.RESULTS: Of 139 Trueprep-extracted DNA, respectively 135 (97%) and 105 (75%) had interpretable results by FL and SL-LPA testing. Of 128 GenoLyse-extracted DNA, all 128 (100%) had interpretable FL-LPA results and 114 (89%) had interpretable SL-LPA results.CONCLUSION: The results obtained in this study indicate that Trueprep-extracted DNA can be used in obtaining valid LPA results. However, the study needs to be conducted on a larger sample size before our recommendations can be used for policy-making decisions.

Frequency characteristics analysis of pipe-to-soil potential under metro stray current interference using continuous wavelet transform method

This study aims to investigate the impact of stray current interference from metro systems on the pipe-to-soil potentials of metallic pipelines, which is closely associated with stray current corrosion. The pipe-to-soil potentials were assessed using coupon testing, while in-situ measurement was conducted to measure the metro leakage currents. The collected field data from the pipe-to-soil potentials and metro leakage current measurements were subjected to a statistical analysis using Continuous Wavelet Transform (CWT) and linear correlation methods. The analysis revealed consistent dominant frequencies of interference at the same test point for both on-potentials and off-potentials conditions, as well as within different time periods. However, variations in dominant frequencies of interference were observed among test points along different sections of the pipeline. Notably, three primary test points exhibited frequencies of 8.3, 8.9, and 7.8 mHz, corresponding to the main interstation travel intervals of neighboring metro lines. Furthermore, the dominant period ranges of interference of metro stray current interference were found to align with the interstation travel interval ranges of the metro lines. When the OVPD acts, the leakage current of the metro station grounding system near the test point has a significant contribution to the amplitude of pipe-to-soil potential fluctuation. These findings highlight the significant role of interstation travel intervals in the periodicity of metro stray current interference. The identified dominant interference frequency ranges can be utilized to determine interference sources and evaluate the extent of metro stray current corrosion.

Boundary node detection in wireless networks with uneven node distribution on open surfaces

Boundary node detection is essential in various application scenarios of wireless networks. However, most previous solutions are only suitable for planar networks with densely and evenly distributed nodes. They cannot satisfy scenarios where nodes are unevenly deployed on open surfaces because the nodes may have different heights, densities, and inter-distances. In this work, we propose a scheme named Surrounding Triangle Validation to detect boundary nodes in wireless networks with uneven node distribution on open surfaces. This solution randomly generates triangles from the 1-hop neighbors of a testing node and validates these triangles. The triangle generation step accepts the triangles with their two endpoints connected by one or more relay nodes in the areas with uneven node density. Then, the generated triangles surrounding the testing node are picked out by point in triangle tests. In the last step, the selected triangles are compared according to the characteristics of a special kind of boundary node to ensure the results of our method. We test our solution in networks with different node densities on several open surfaces. Simulation results show that our method works effectively. It detects boundary nodes more correctly than previous solutions.

Relationship between age, menstrual cycle, and length of menstruation with anemia in adolescent girls in the Gresik district

Anemia in adolescents is defined as a low hemoglobin level (less than 12g/dl) in adolescent blood. The incidence of anemia in Indonesia is still quite high. In adolescents, anemia is more prevalent due to growth spurt, onset of menarche, poor nutrition, and poverty. Age has a significant relationship with the incidence of anemia in adolescents, especially in older girls. The menstrual cycle and length of menstruation play an important role in the amount of blood that flows out. This study aims to analyze the relationship between age, menstrual cycle, and length of menstruation with anemia in adolescent girls in the Gresik District. The type of research was quantitative analytic observational cross-sectional design. Respondents consisted of 661 adolescent girls aged 10-19 years old in elementary, junior high, and senior high school held UKS program in Gresik District. Hb data was obtained by POCT (Point of Care Test) and other data was obtained by questionnaires via google form. The result showed that 29% were diagnosed with anemia, and 71% were not. The category of adolescents was found 8.3% in early, 59.8% in middle, and 31.9% in late adolescents. Menstrual cycle was found 54.6% in the short cycle, 40.7% normal cycle, and 4.7% long cycle category. The length of menstruation was 1.1% in short category, 74.1% normal category, and 24.8% long category. The results of statistical using the chi-square test in analyzing the relationship between age with anemia obtained pvalue=0,065, menstrual cycle with anemia obtained pvalue=0,128, and length of menstruation with anemia obtained pvalue=0,330. There is no correlation between age, menstrual cycle, and length of menstruation with anemia in adolescent girls in Gresik District.

Detection of Listeria monocytogenes using an immunochromatographic point of care test based on anti-internalin A and B antibodies and a nano-biotinylated detection complex

The detection of Listeria monocytogenes, a Gram-positive food-borne bacterium, helps prevent listeriosis outbreaks, an invasive disease with high mortality rates among immunocompromised individuals. Microbiological culture methods are time-consuming, requiring laboratory infrastructure while molecular techniques are expensive and require complex equipments. We have developed a point of care test (POCT) based on lateral flow immunochromatography, combining anti-Internalin A and B antibodies and the biotin-streptavidin system into a nano-biotinylated detection complex. The new lateral flow prototype presented the following visual limit of detection (LOD):102 CFU/mL in pure cultures of L. monocytogenes; 102 CFU/mL or/25 g in samples of artificially contaminated milk, lettuce, mozzarella cheese, hamburger. Quantitative analysis indicated LOD between 102–10 CFU/mL in pure cultures of L. monocytogenes. The prototype showed 100% specificity when tested with pure cultures of Listeria innocua, Bacillus cereus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Micrococcus luteus, Serratia marcescens, Enterobacter aerogenes, Enterococcus faecalis, Enterobacter cloacae Salmonella Enteritidis, Salmonella Typhimurium and Klebsiella pneumoniae. Unlike commercially available tests, this prototype showed detection capacity closer to the minimum L. monocytogenes infectious dose. Therefore, this prototype represents a promising POCT candidate allowing the quick, specific, and sensitive detection of L. monocytogenes in food matrices and on food production platforms.

Point of care detection of SARS-CoV-2 antibodies and neutralisation capacity-lateral flow immunoassay evaluation compared to commercial assay to inform potential role in therapeutic and surveillance practices.

As the COVID-19 pandemic moves towards endemic status, testing strategies are being de-escalated. A rapid and effective point of care test (POCT) assessment of SARS-CoV-2 immune responses can inform clinical decision-making and epidemiological monitoring of the disease. This cross-sectional seroprevalence study of anti-SARS-CoV-2 antibodies in Irish healthcare workers assessed how rapid anti-SARS-CoV-2 antibody testing can be compared to a standard laboratory assay, discusses its effectiveness in neutralisation assessment and its uses into the future of the pandemic. A point of care lateral flow immunoassay (LFA) detecting anti-SARS-CoV-2 spike (S)-receptor binding domain (RBD) neutralising antibodies (Healgen SARS-CoV-2 neutralising Antibody Rapid Test Cassette) was compared to the Roche Elecsys/-S anti-SARS-CoV-2 antibody assays and an in vitro surrogate neutralisation assay. A correlation between anti-spike (S), anti-nucleocapsid (N) titres, and in vitro neutralisation was also assessed. 1,777 serology samples were tested using Roche Elecsys/-S anti-SARS-CoV-2 assays to detect total anti-N/S antibodies. 1,562 samples were tested using the POC LFA (including 50 negative controls), and 90 samples were tested using an in vitro ACE2-RBD binding inhibition surrogate neutralisation assay. The POCT demonstrated 97.7% sensitivity, 100% specificity, a positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 61% in comparison to the commercial assay. Anti-S antibody titres determined by the Roche assay stratified by the POC LFA result groups demonstrated statistically significant differences between the "Positive" and "Negative" LFA groups (p < 0.0001) and the "Weak Positive" and "Positive" LFA groups (p < 0.0001). No statistically significant difference in ACE2-RBD binding inhibition was demonstrated when stratified by the LFA POC results. A positive, statistically significant correlation was demonstrated between the in vitro pseudo-neutralisation assay results and anti-S antibody titres (rho 0.423, p < 0.001) and anti-N antibody titres (rho = 0.55, p < 0.0001). High sensitivity, specificity, and PPV were demonstrated for the POC LFA for the detection of anti-S-RBD antibodies in comparison to the commercial assay. The LFA was not a reliable determinant of the neutralisation capacity of identified antibodies. POC LFA are useful tools in sero-epidemiology settings, pandemic preparedness and may act as supportive tools in treatment decisions through the rapid identification of anti-Spike antibodies.

A-386 Performance assessment of Point of care testing for blood glucose: a 5 year review of EQA data

Abstract Introduction WEQAS is the largest External Quality Assessment (EQA) provider for the Point of Care Testing (POCT) market within the UK supplying samples and assessment to over 30 000 sites per month with over 20 Programmes across the entire Health care sector. All the Programmes are accredited to ISO 17043.The aim of the programme is to provide support to POCT co-ordinators, to identify non compliant sites and improve the analytical performance of users. Most of the programmes are designed to allow the full assessment of all the devices within the organisation at either monthly, bimonthly or quarterly intervals. A Co-ordinator in each organisation is given a Group Administrator function for the EQA website and maintains the database for its own organisation. The role of performance surveillance is therefore devolved to each individual Co-ordinator at a local level and monitored nationally by the EQA organiser. The powerful database gives POCT Co-ordinators a wealth of information on method and analyser performance both within their own organisation and between organisations. Organisation performance summary reports, distribution letters, non-compliance reports, poor performance reports and cumulative reports are generated from one system. The POCT Users are also provided with a simple traffic light system with clear action limits. For the POCT glucose programme one sample is distributed each month with samples covering a range of 2 to 28 mmol/l annually. Methods A review of performance was undertaken between January 2018 and January 2023 for the POCT glucose Programmes for a selection of devices. Devices that were no longer available were excluded as were devices with &amp;lt;50 users in the group. This represented data from 10 360 devices per month in 2018 and 12 277 in 2023. Performance was assessed as the coefficient of variation (CV%) for the device group after outlier exclusion and calculated for a wide range of glucose concentrations. Results For devices with CV less than 5% in 2018 there was generally no further improvement in performance, however at a glucose of 2 mmol/L an improvement in performance of 0.5to 3.5% was observed for the other devices. In 2018 CVs ranged from 3.7 to 12% and 3.1 to 8.3%% at 2.5 and 26 mmol/L respectively compared with 4 to 10.3% and 3.3 to 7.2% in 2022. Conclusion Although there were numerous examples where EQA identified poor performance at an individual user level, there was little evidence to suggest that the performance of POCT glucose devices had improved significantly over the last 5 years.

A-179 Implementation of an Electronic Competency Evaluation System for Point of Care Testing

Abstract Background Management of training and competency evaluation for point of care testing personnel is essential to hospital operations. Typically, documentation for training and competency of point of care operators is a paper based manual process and managed by the POCT team. The responsibilities include maintaining these records for the duration of employment and thereafter and retrieving records for regulatory inspections. It is a challenge for any POCT team in a hospital system with a high volume of operators. In an effort to streamline this process, an electronic training and competency format for the operators of point of care glucose meter was developed and implemented in our hospital system. Method Initial training and competency requires in person delivery which must capture specific elements of competency and must be traceable to the trainer and trainee. Leveraging a survey based online training platform (Qualtrics) as the repository of the training record, the paper based training checklist was converted to an online format accessed via QR (Quick Response) code. Delivery of the training is performed by a certified trainer or preceptor under observation. The training checklist and competency quiz are documented directly in Qualtrics capturing all of the data required for traceability. The evaluation record of each new trainee is available to the POCT Team in real time. Results The online format of initial training and competency was validated by comparing the paper based version to the electronic version. Functionality of the electronic version was confirmed and accuracy of the checklist answers were validated. This electronic format was implemented for initial operator training and evaluation in January 2023. Over 150 trainees have successfully completed the electronic training checklist and competency quiz. Discussion and Conclusion The implementation of an electronic evaluation tool for operators of point of care blood glucose testing has streamlined the process of documentation management in a secure, reliable and transparent way. It also helps to standardize the training process and minimize errors related to a manual process. These documents are readily available and can be retrieved upon request. The implementation of the electronic training evaluation system through Qualtrics coupled with our existing electronic re-certification process will allow us to transition to a fully paperless evaluation/documentation workflow.

A-374 Analytical Performance Assessment and Comparison of Point of Care Testing (POCT) Devices for Blood Lipids Measurements

Abstract Background Cardiovascular diseases (CVDs) are the leading cause of death in the U.S. and worldwide. According to the World Health Organization (WHO), worldwide, 85% of CVD deaths are due to heart disease and strokes, and over 75% occur in low- and middle-income countries (LMICs). Early detection and treatment are key to preventing the consequences of CVD. Point-of-care testing (POCT) devices offer alternatives to screening large populations for CVD risk. Although POCT are increasingly used for screening, only few information is available about their accuracy and reliability. Methods Eight POCT devices for blood lipids that previously successfully participated in the CDC CVD Biomarker Standardization Programs were used in this preliminary study. The analytical performance for all eight devices was assessed using split sample comparisons to the CDC reference measurement procedures for measurements performed in whole blood (WB) and serum. Specifically, the accuracy of total cholesterol (TC) was determined in WB and serum. The accuracy of high-density lipoprotein-cholesterol (HDL-c), and low-density lipoprotein-cholesterol (LDL-c) was determined in serum. The precision of TC, HDL-c, LDL-c, and triglycerides (TG) was determined in WB and serum. Results The reference values of the specimens from 20 donors ranged between 154–279 mg/dL, 36.9–109 mg/dL, and 71.1–182 mg/dL for TC, HDL-c, and LDL-c in serum, and between 145–210 mg/dL for TC in WB. Preliminary assessments found that the mean bias for each instrument ranged from -7.86%–13.82% and from -11.90%–3.24% for TC in WB and serum, respectively. For serum HDL-c samples, the mean bias ranged from −6.81%–15.43%. The mean bias for serum LDL-c samples ranged from −22.40% to 3.08%. For three devices, approximately 30% of the WB measurements and approximately 50% of the serum measurements were reported as outside of the measurement range. The mean imprecision for each instrument ranged from 2.2%–13.75% and from 1.88%–11.76% for TC in WB and serum, respectively. For HDL-c, the mean imprecision ranged from 5.36%–23.21% and from 2.30% to 26.69% in WB and serum, respectively. The mean imprecision ranged from 4.82%–20.34% and from 3.06%–20.54% for LDL-c in WB and serum, respectively. For TG, the mean imprecision ranged from 5.78%–23.91% and from 1.71%–11.02% in WB and serum, respectively. Conclusion These preliminary findings about the analytical performance of POCT devices indicate notable differences in accuracy and precision for lipids measured in WB and serum, with serum measurements being more likely within performance requirements than WB measurements. Some devices appear to be more likely to report values outside the measurement range even though reference values are within the measurement range of the device. Further studies to verify these preliminary findings with more individual donor samples are underway.

A-378 Clinical Evaluation and Implementation of Rapid COVID-19 Antigen Test in Qatar

Abstract Background In March, the World Health Organization (WHO) declared COVID-19 as a global public health emergency. To curb the spread of virus, timely detection of infected patients and screening of suspected cases in massive population posed a challenge for the healthcare system. Rapid antigen tests (RAT) were high in demand as a fast, accurate and cost-effective screening tool to increasing the testing capacity. In this crucial timing, clinical evaluation and procurement of available COVID-19 RAT following the World Health Organization (WHO) guidelines was a huge challenge for Point of Care testing (POCT) department. The aim of this study is to highlight the challenges overcame in establishing a Point-of-care COVID-19 testing system including personnel training and building a compatible Laboratory Information System (LIS) upholding Hamad Medical Corporation (HMC) cyber security regulation. Methods Three regulatory approved RATs were evaluated against real-time polymerase chain reaction (RT-PCR) and analytical performance were verified. Maintaining the Clinical Laboratory Improvement Amendments (CLIA) and College of American Pathologist (CAP) standards for COVID-19 waived testing, POCT team initiated to conduct practical and educational training vastly through online platforms and face to face sessions. We utilized the extendable LIS functionality for fast medical decisions in hospitals and enabled “reason of testing” feature in Qatar's COVID-19 tracking application. Results Our performance verification showed 98.0% sensitivity and 100% specificity for PanbioTM COVID-19 RAT, 98.0% sensitivity and 100% specificity for Quidel SOFIA2 COVID-19 RAT and Roche COVID-19 RAT yielded a sensitivity of 97.0% and specificity of 100%. Total of 291 training sessions were conducted for 9710 clinical staffs across 17 HMC facilities and 185 private clinics. Using LIS and POC middleware features, obvious increment in RAT of more than 509 tests per day has been reported in a single emergency unit. Overall, 5.5% decrement in incorrect patient identification data using QUIDEL SOFIA2 automated device and LIS functions was recorded in laboratory quality indicator data. COVID-19 tracking application was linked to antigen results for contact tracing, isolating, and breaking the chain of transmission. Conclusion The methods established for the COVID-19 implementation showed acceptable performance fulfilling the elements of HMC product procurement specification and CAP Accreditation standards. Synergic actions of HMC-POCT with supportive laboratory management aided prompt decision making to optimize patient management and added efficiency to the public health control measures in Qatar.

B-232 Versatile, Extraction-Free Nucleic Acid Sample Preparation in 15 Seconds Via Hyperbaric Heating

Abstract Nucleic acid extraction-based PCR sample prep is currently limited by long processing times, liquid transfers, kit cost, and lab storage requirements. Extraction-free approaches enable streamlined sample prep, but lack sensitivity compared to extraction-based methods. We studied several sample types to demonstrate the effectiveness of a novel 15-second Hyperbaric Heating (HBH) process to prepare nucleic acids for PCR. HBH exposes the sample to a short duration, high temperature environment to effectively lyse organisms and denature PCR inhibitors such as nucleases in seconds. Samples are introduced and sealed in a pressure-tight metallic vessel, which is then heated in seconds using magnetic induction. Within the sealed metallic vessel, the vaporization of the aqueous sample raises the internal pressure, enabling an internal temperature higher than 100°C to be achieved. Chelating agents and other proteins in HBH also protect the target nucleic acids from fragmentation. Post HBH, the sample is ready for direct PCR amplification without further dilution or extraction. Efficacy of HBH for efficient PCR amplification was tested against commercial kits. HBH was applied to viral, bacterial, eukaryotic, and fungal organisms. For SARS-CoV-2, HBH detected down to 250 viral copies/mL. Additionally, HBH outperformed commercial kits for PCR sample prep of Candida albicans and Bacillus subtilis. HBH is a generalizable sample prep technology with sensitivity comparable to that of current extraction kits. We have applied HBH to a multitude of organisms and have demonstrated that HBH can be employed as a rapid and comprehensive nucleic acid prep approach for applications that involve PCR amplification post sample prep. Future integration of HBH in devices suitable for point of care molecular testing are underway. We also envision HBH to be a useful, generalizable sample prep method for the molecular lab in applications where cost, simplicity, and speed are essential for preparing nucleic acids for amplification.

B-328 Analytical Performance of a Screening Test for Lead Using Dried Blood Spots and ICP-MS

Abstract Introduction There is no safe blood lead levels (BLL) in children and exposure can cause irreversible neurological harm. In 2021, the CDC decreased the blood lead reference value (BLRV) to 3.5 ug/dL from 5.0 ug/dL, based on the 97.5th percentile of BLL among US children under 5 years of age. Despite this, lead poisoning disproportionately affects Black children, those below poverty levels, and living in houses built before 1978. The American Academy of Pediatrics recommends targeted screening for BLL in children aged 12–24 months living in high prevalence areas. Children enrolled in Medicaid also require screening by 24 months of age. Only one-third of children who require screening receive it and lead screening declined by &amp;gt;50% during the COVD-19 pandemic. Quality improvement strategies have included electronic health record alerts and point of care testing. To improve screening rates in our pediatric population, we developed a screening method utilizing dried blood spot (DBS) cards. This study aimed to validate the accuracy and precision of this screening method with emphasis on the performance around the BLRV cut-offs, which would be used to determine the need to follow up with a confirmatory venous lead test. Methods The method was calibrated using certified reference material traceable to NIST SRM 3128 (VHG labs, Manchester, NH, USA) in whole blood. The calibrators, controls and patient samples were spotted onto Whatman 903 cards. A 6 mm filter paper disc in extraction buffer was vortexed, allowed to sit at room temperature for 30 min and centrifuged. The samples were analyzed on the Thermo Fisher iCAP RQ and TQ (Whaltman, MA) in kinetic energy discrimination mode. The assay has a linear range of 1–100 µg/dL, and the recovery ranged from 92%–102%. We evaluated this method for reproducibility, and accuracy across the measurement range. In this study, we focused on the reproducibility and accuracy of DBS at lead concentrations around the BLRV cut-offs. We used in 2 samples spiked with NIST CRM 3128 (Inorganic Ventures, Christiansburg, VA, USA) analyzed 10 times over 3 days and 13 leftover patient samples run over at least 5 days. The total allowable error was 2 µg/dL or 10%. Results In two samples spiked to BLL of 3.5 and 3.9 µg/dL, interday precision (n = 10) ranged from 3.4% to 17.4% (SD 0.1–0.7) in samples run for 3 days. Removal of an apparent outlier decreased the %CV ranged observed to &amp;lt;8.5%. The average bias for each day ranged from 0.1 to 0.6 µg/dL. In 13 patient samples with concentrations around the BLRV ranging from 1.4 to 5.8 µg/dL, the coefficient of variation (CV) ranged from 0.2% to 32% with the largest SD at 0.8 µg/dL. The average bias for this sample set was -0.3 (11.7%). Conclusion The assay’s analytical performance is sufficient for screening purposes, but the clinical performance and the impact of introducing this test to enhance screening rates during 1 and 2 years well visits need to be evaluated further.