Evaluation of Coefficients of Variation for Clinical Chemistry Tests Based on Internal Quality Control Data Across 5,425 Laboratories in China From 2013 to 2022

Background

Clinical chemistry tests are most widely used in clinical laboratories, and diverse measurement systems for these analyses are available in China. We evaluated the imprecision of clinical chemistry measurement systems based on internal QC (IQC) data.

Methods

IQC data for 27 general chemistry analytes were collected in February each year from 2013 to 2022. Four performance specifications were used to calculate pass rates for CVs of IQC data in 2022. Boxplots were drawn to analyze trends of CVs, and differences in CVs among different groups were assessed using the Mann-Whitney U-test or Kruskal-Wallis test.

Results

The number of participating laboratories increased significantly from 1,777 in 2013 to 5,425 in 2022. CVs significantly decreased for all 27 analytes, except creatine kinase and lipase. Triglycerides, total bilirubin, direct bilirubin, iron, and γ-glutamyl transferase achieved pass rates >80% for all goals. Nine analytes with pass rates <80% based on 1/3 allowable total error were further analyzed; the results indicated that closed systems exhibited lower CVs than open systems for all analytes, except total protein. For all nine analytes, differences were significant between tertiary hospitals and non-tertiary hospitals and between accredited and non-accredited laboratories.

Conclusions

The CVs of IQC data for clinical chemistry have seen a continuous overall improvement in China. However, there is ample room for imprecision improvement for several analytes, with stricter performance specifications.

Measurement uncertainty estimation of free drug concentrations in clinical laboratories using equilibrium dialysis

OBJECTIVES

Developing procedures based on equilibrium dialysis (ED) that allow measuring the free drug concentration in plasma improves therapeutic drug monitoring (TDM) in those cases where its measurement is justified. However, this procedure requires specific sample preparation and presents different pitfalls, which are not error-free. As with any result provided by a clinical laboratory, this one should be as accurate as possible to allow a correct clinical interpretation. The measurement uncertainty (MU) is a parameter that enables the accuracy of results to be known, and that is mandated by ISO 15189. Herein, this study suggests how the MU for the results of the free drug concentrations in serum could be estimated when an ED is used.

METHODS

A combination of the top-down and bottom-up approaches was used to estimate the MU based on the ISO/TS 20914:2019 and JCGM 100:2008 guidelines, including the concentration of free phenytoin in serum, as an example. Different scenarios were incorporated considering or not a significant bias related to the primary drawbacks of ED: the non-specific binding, the volume shift effect and the Gibbs-Donnan effect.

RESULTS

The expanded uncertainties estimated ranged between 13.0 and 30.9 %. The highest MU corresponded to the free drug concentrations in serum results when significant biases related to the volume shift and Gibbs-Donnan effects exist.

CONCLUSIONS

A detailed estimation of MU for free drug concentrations is presented using ED, considering different scenarios. This study could stimulate clinical laboratories to perform MU studies and its application in TDM.

Performances and determinants of proficiency testing in clinical laboratory services at comprehensive specialized hospitals, northwest Ethiopia

Proficiency testing (PT) is an impartial laboratory performance-evaluating system using an independent body. It is a mandatory accreditation requirement and means for improving the laboratory's performance. The study aimed to evaluate the performance of PT, with a focus on identifying and discussing determinants that influence PT performance at comprehensive specialized hospitals in northwest Ethiopia. A retrospective cross-sectional study was carried out from 2020 to 2022. Using a convenient sampling technique, laboratory tests with recorded PT results in each hospital laboratory were included. A data collection template and customized checklists were used to collect the data. Epi Data Version 3.1 for data entry and STATA Version 14.1 for cleaning and analysis were used. Binary logistic regression analyses were used. Variables with p < 0.05 in the multivariable logistic regression were considered to be statistically significant. Over nine cycles, 3807 PT challenges were distributed. The total failure rate of the laboratories was 32.4%, with a peak failure rate of 40.3% in 2020, after which the failure rate was decline to 20.6% in 2022. Among the five laboratory sections, molecular biology had the lowest failure rate (22.2%), while microbiology had the highest failure rate (56.5%). Multivariate logistic regression revealed that PT results reported without appropriate unit of measurement (AOR 7.5), lack of corrective action for PT nonconformance (AOR 7.1), and reagent unavailability (AOR 6.1) had significant effects on PT performance (p < 0.001). The results of this study showed that the overall performance of the laboratory was lower. Reporting PT results without appropriate units of measurement and not taking corrective action for PT nonconformance were the major aggravating factors for high failure rates.

ICSH review of internal quality control policy for blood cell counters

INTRODUCTION

This paper is a report of an ICSH review of policies and practices for internal quality control (IQC) policy for haematology cell counters among regulatory bodies, cell counter manufacturers and diagnostic laboratories. It includes a discussion of the study findings and links to separate ICSH guidance for such policies and practices. The application of internal quality control (IQC) methods is an essential pre-requisite for all clinical laboratory testing including the blood count (Full Blood Count, FBC, or Complete Blood Count, CBC).

METHODS

The ICSH has gathered information regarding the current state of practice through review of published guidance from regulatory bodies, a questionnaire to six major cell counter manufacturers (Abbott Diagnostics, Beckman Coulter, Horiba Medical Diagnostic Instruments & Systems, Mindray Medical International, Siemens Healthcare Diagnostics and Sysmex Corporation) and a survey issued to 191 diagnostic laboratories in four countries (China, Republic of Ireland, Spain and the United Kingdom) on their IQC practice and approach to use of commercial IQC materials.

RESULTS

This has revealed diversity both in guidance and in practice around the world. There is diversity in guidance from regulatory organizations in regard to IQC methods each recommends, clinical levels to use and frequency to run commercial controls, and finally recommended sources of commercial controls. The diversity in practice among clinical laboratories spans the areas of IQC methods used, derivation of target values and action limits used with control materials, and frequency of running commercial controls materials.

CONCLUSIONS

These findings and their implications for IQC Practice are discussed in this paper. They are used to inform a separate guidance document, which proposes a harmonized approach to address the issues faced by diagnostic laboratories.

Estimation of Numbers of Testing Personnel and Test Volume in the Clinical Laboratory Improvement Amendments of 1988 Certificate of Accreditation and Certificate of Compliance Laboratories in the United States

CONTEXT.—

Two major categories of laboratories performing nonwaived testing under the Clinical Laboratory Improvement Amendments of 1988 (CLIA) are the Certificate of Accreditation (CoA) and Certificate of Compliance (CoC) laboratories. Accreditation organizations collect more detailed laboratory personnel information than the Centers for Medicare & Medicaid Services (CMS) Quality Improvement and Evaluation System (QIES).

OBJECTIVE.—

To estimate total numbers of testing personnel and testing volumes in CoA and CoC laboratories, by laboratory type and state.

DESIGN.—

We developed a statistical inference method by using the respective correlations between testing personnel counts and test volume by laboratory type.

RESULTS.—

QIES reported 33 033 active CoA and CoC laboratories in July 2021. We estimated testing personnel to be 328 000 (95% CI, 309 000-348 000), which is supported by the count of 318 780 reported by the US Bureau of Labor Statistics. There were twice as many testing personnel in hospital laboratories as in independent laboratories (158 778 versus 74 904, P < .001). Independent laboratories had the highest test volume per person, which was twice as high as physician office laboratories (62 228 versus 30 102, P < .001). Hospital and independent laboratories comprised 34% of all CoA and CoC laboratories but performed the largest portion of testing (81%). Physician office laboratories, accounting for 44% of all CoA and CoC laboratories, performed a comparatively low proportion of total tests (9%).

CONCLUSIONS.—

Numbers of testing personnel vary considerably by laboratory type and across states. These data can provide valuable insight when assessing laboratory workforce training needs and planning for public health emergencies.

ICSH guidance for internal quality control policy for blood cell counters

This paper is a description of the ICSH guidance for internal quality control (IQC) policy for blood cell counters. It follows from and links to a separate ICSH review for such policies and practices. The ICSH has gathered information regarding the current state of practice through review of published guidance from regulatory bodies, a questionnaire to six major cell counter manufacturers and a survey issued to 191 diagnostic laboratories in four countries (China, the Republic of Ireland, Spain, and the United Kingdom) on their IQC practice and approach to the use of commercial IQC materials. This has revealed diversity both in guidance and in practice around the world. There is diversity in guidance from regulatory organizations in regard to IQC methods each recommends, clinical levels to use and frequency to run commercial controls, and finally recommended sources of commercial control materials. The diversity in practice among clinical laboratories spans the areas of IQC methods used, derivation of target values, and action limits used with commercial control materials, and frequency of running commercial controls materials. These findings and their implications for IQC Practice are addressed in this guidance document, which proposes a harmonized approach to address the issues faced by diagnostic laboratories.

From volume to value: a watershed moment for the clinical laboratory

The clinical laboratory is often evaluated for the volume of testing. However, it is undeniable that laboratory tests affect clinical decision-making and are included in many clinical guidelines, meaning their contribution to determining clinical outcomes. Therefore, the clinical laboratory professional has the task of enhancing laboratory tests by optimizing the request and reporting phase and addressing patient outcomes. This opinion paper, presenting practical examples of managing value-based health care in the clinical laboratory context, underlines the need to shift towards value-based management to optimize outcome-based health care.

Genetic sex validation for sample tracking in next-generation sequencing clinical testing

OBJECTIVE

Data from DNA genotyping via a 96-SNP panel in a study of 25,015 clinical samples were utilized for quality control and tracking of sample identity in a clinical sequencing network. The study aimed to demonstrate the value of both the precise SNP tracking and the utility of the panel for predicting the sex-by-genotype of the participants, to identify possible sample mix-ups.

RESULTS

Precise SNP tracking showed no sample swap errors within the clinical testing laboratories. In contrast, when comparing predicted sex-by-genotype to the provided sex on the test requisition, we identified 110 inconsistencies from 25,015 clinical samples (0.44%), that had occurred during sample collection or accessioning. The genetic sex predictions were confirmed using additional SNP sites in the sequencing data or high-density genotyping arrays. It was determined that discrepancies resulted from clerical errors (49.09%), samples from transgender participants (3.64%) and stem cell or bone marrow transplant patients (7.27%) along with undetermined sample mix-ups (40%) for which sample swaps occurred prior to arrival at genome centers, however the exact cause of the events at the sampling sites resulting in the mix-ups were not able to be determined.

The Role of Artificial Intelligence for Providing Scientific Content for Laboratory Medicine

BACKGROUND

Artificial intelligence (AI) promises to become an important tool in the practice of laboratory medicine. AI programs are available online that can provide concise medical and laboratory information within seconds after a question is submitted.

METHODS

We posed the following contemporary and relevant question for clinical chemists using an AI program: "Should labs eliminate CK-MB testing?" The results of this inquiry were critically reviewed by a cardiologist, emergency department physician, and clinical laboratorians for accuracy and appropriateness.

RESULTS

An AI report answering this question was generated within 15 s. The experts felt that the information was inaccurate with the statements that CK-MB results are released earlier than cardiac troponin (cTn), and are more useful for detection of myocardial injury in patients with renal insufficiencies. The summary omitted discussion on the ongoing debate for periprocedural detection of acute myocardial infarction (MI), the perceived value for detection of reinfarction, the value in risk stratification compared to cTn, the economic justification for testing both CK-MB and cTn, and medicolegal aspects of testing when results are discordant.

CONCLUSIONS

At this time, AI does not appear to be ready to be used by clinical laboratories for answering important practice questions.

Current practice and recommendations for managing transgender patient data in clinical laboratories in the United Kingdom and Republic of Ireland

BACKGROUND

Transgender people may avoid seeking medical care due to previous negative experiences and fear of discrimination. Clinical laboratories can contribute to a poor patient experience and clinical outcome when the design and functionality of laboratory information management systems (LIMS) do not consider the needs of transgender patients. This survey aimed to capture current practices in United Kingdom and Republic of Ireland clinical laboratories concerning how transgender patient data and test requests are managed throughout the total testing process.

METHODS

An anonymous survey was distributed to clinical laboratory professionals in November 2021. Thirty-three questions covered how gender variables are recorded for transgender patients and used to inform gender-specific calculations, test access, and reference intervals (RIs).

RESULTS

Of the 66 respondents, 70% were based in laboratories in England, with a majority of laboratories having ISO 15189 accreditation and processing 1000-10,000 blood samples daily. Eighty-five percent stated that their LIMS had a single field recording sex or gender information. Forty-three percent did not limit test access based on gender, but 68% did not append RIs for patients with unknown or indeterminate gender.

CONCLUSIONS

This survey was the first to quantify how clinical laboratories manage sex and gender information and report results for transgender and non-binary patients, and details several key recommendations based on the survey responses.

A call-to-action for energy conservation and sustainability in the clinical laboratory: Experiences from the University of Padova

OBJECTIVES

Healthcare has a considerable environmental impact, yet it has been largely overlooked. Clinical laboratories, in particular, consume significantly more energy and water per unit area compared to standard office buildings. It is crucial to raise awareness among laboratories about the significance of embracing eco-friendly practices. Numerous energy-saving measures do not incur additional costs but necessitate a shift in organizational culture and mindset.

DESIGN & METHODS

This paper conducts a cost-benefit analysis of energy consumption at the Laboratory Medicine Unit of University Hospital of Padova, beginning with laboratory refrigerators and freezers.

RESULTS

The need to rationalize the existing units, especially the combined refrigerators-freezers, and reorganize the contents of the Ultra-Low Temperature freezers with an energy-saving perspective has emerged.

CONCLUSIONS

By implementing these practices, this initiative can gradually expand to encompass more green activities in the future.

The LEAP Checklist for Laboratory Evaluation and Analytical Performance Characteristics Reporting of Clinical Measurement Procedures

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the Laboratory Evaluation and Analytical Performance Characteristics (LEAP) checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

Point of Care Molecular Testing: Current State and Opportunities for Diagnostic Stewardship

Inappropriate ordering practices, either under or over ordering of diagnostic tests, are recognized problems with possible negative downstream consequences. As the menu of clinical tests, especially molecular tests grows, it is becoming increasingly important to provide guidance to providers on the appropriate utilization. Diagnostic stewardship programs have been established at many institutions to help direct the appropriate utilization of laboratory testing to ultimately guide patient management and treatment decisions. Many molecular tests have now received Clinical Laboratory Improvement Amendments (CLIA)-waived status for use in a point-of-care (POC) setting; however, parallel diagnostic stewardship programs have not been established to help guide providers on how best to use these tests. In this article, we will discuss the available molecular POC tests and opportunities and challenges for establishing diagnostic stewardship programs for molecular testing performed in the POC setting.

Taking Center Stage: Clinical Laboratory Leading Diagnostic Stewardship Efforts

This article will discuss diagnostic stewardship from the perspective of those who are just starting, or have recently started, a diagnostic stewardship effort. This document will provide guidance on how to identify opportunities for intervention and tools that can be used to affect change. Specifically, we will discuss key components of a diagnostic stewardship committee, referral laboratory testing, prior authorization, miscellaneous test orders, establishing a laboratory test formulary, and conclude with some specific examples of interventions that can be considered.

Diagnostic Stewardship for Multiplex Respiratory Testing: What We Know and What Needs to Be Done

Syndromic respiratory panels are now widely available in clinical microbiology laboratories and health care institutions. These panels can rapidly diagnose infections and detect antimicrobial resistance genes allowing for more rapid therapeutic optimization compared to standard microbiology approaches. However, given reimbursement concerns and limitations of multiplex molecular testing and results interpretation, maximum clinical utility and positive clinical outcomes depend on active diagnostic stewardship. Here, the authors review clinical outcomes of both upper and lower respiratory panels and present diagnostic stewardship strategies for optimal use of respiratory panels.

Algorithm of differential diagnosis of anemia involving laboratory medicine specialists to advance diagnostic excellence

OBJECTIVES

Anemia is a severe global public health issue. Testing practices for anemia suggest overuse of screening laboratory tests and misinterpretation of studies even in "easy-to-diagnose" underlying causes, leading to late diagnoses and missed treatment opportunities. We aimed to develop a complete and efficient algorithm for clinical pathologists and laboratory medicine physicians for the differential diagnosis of anemia.

METHODS

Comprehensive literature search encompassing original articles, studies, reviews, gold standard books, and other evidence.

RESULTS

We created a complex algorithm, primarily for clinical pathology/laboratory use, that explores all major and several rare causes of anemia in an efficient and evidence-based manner. The algorithm includes gold-standard diagnostic laboratory tests available in most clinical laboratories and indices that can be easily calculated to provide an evidence-based differential diagnosis of anemia.

CONCLUSIONS

The diagnostic strategy combines previously available diagnostic tests and protocols in an efficient order. Clinical pathologists following the algorithm can independently provide valuable diagnostic support for healthcare providers. Clinical pathologists providing complete differential diagnostic services with the proposed algorithm may create an opportunity for an advanced diagnostic service that supports diagnostic excellence and helps patients receive a timely diagnosis and early treatment opportunities.

FDA's proposed rule for the regulation of laboratory-developed tests

In October 2023, the Food and Drug Administration (FDA) released a proposed rule that ends enforcement discretion for laboratory-developed tests (LDTs). The FDA's proposal outlines a five-stage implementation to begin regulating LDTs as they do for commercial in vitro diagnostics (IVDs), including modified FDA-approved/cleared tests. We outline here concerns from the clinical and public health microbiology laboratory perspective. It is our opinion that LDTs performed by individual Clinical Laboratory Improvement Amendments-certified diagnostic laboratories should not be regulated in the same way as commercial IVDs. This rule, if finalized, will negatively impact the diagnostic services currently offered by clinical and public health laboratories and, therefore, patients and the providers who care for them. Ending enforcement discretion will likely stifle diagnostic innovation and decrease access to diagnostic testing and health equity. Furthermore, the lack of infrastructure, including personnel and funding, at the FDA and diagnostic laboratories to support the required submissions for review is an obstacle. Like the FDA, diagnostic laboratories prioritize patient safety, accurate clinical diagnostics, and health equity. Since the scope of the LDT landscape is currently unknown, we are supportive of a registration process, along with non-burdensome adverse event reporting, to first understand the scope of clinical use of LDTs and any associated safety concerns. Any regulatory rule should be based on data that have been gathered systematically, not anecdotes or case reports. A rule must also balance the potential negative impact to patient care with realistic safety risks for infectious disease diagnostics.

Development and Validation of a Risk Score Predicting Death Without Transplant in Adult Heart Transplant Candidates

Importance

The US heart allocation system prioritizes medically urgent candidates with a high risk of dying without transplant. The current therapy-based 6-status system is susceptible to manipulation and has limited rank ordering ability.

Objective

To develop and validate a candidate risk score that incorporates current clinical, laboratory, and hemodynamic data.

Design, Setting, and Participants

A registry-based observational study of adult heart transplant candidates (aged ≥18 years) from the US heart allocation system listed between January 1, 2019, and December 31, 2022, split by center into training (70%) and test (30%) datasets. Adult candidates were listed between January 1, 2019, and December 31, 2022.

Main Outcomes and Measures

A US candidate risk score (US-CRS) model was developed by adding a predefined set of predictors to the current French Candidate Risk Score (French-CRS) model. Sensitivity analyses were performed, which included intra-aortic balloon pumps (IABP) and percutaneous ventricular assist devices (VAD) in the definition of short-term mechanical circulatory support (MCS) for the US-CRS. Performance of the US-CRS model, French-CRS model, and 6-status model in the test dataset was evaluated by time-dependent area under the receiver operating characteristic curve (AUC) for death without transplant within 6 weeks and overall survival concordance (c-index) with integrated AUC.

Results

A total of 16 905 adult heart transplant candidates were listed (mean [SD] age, 53 [13] years; 73% male; 58% White); 796 patients (4.7%) died without a transplant. The final US-CRS contained time-varying short-term MCS (ventricular assist-extracorporeal membrane oxygenation or temporary surgical VAD), the log of bilirubin, estimated glomerular filtration rate, the log of B-type natriuretic peptide, albumin, sodium, and durable left ventricular assist device. In the test dataset, the AUC for death within 6 weeks of listing for the US-CRS model was 0.79 (95% CI, 0.75-0.83), for the French-CRS model was 0.72 (95% CI, 0.67-0.76), and 6-status model was 0.68 (95% CI, 0.62-0.73). Overall c-index for the US-CRS model was 0.76 (95% CI, 0.73-0.80), for the French-CRS model was 0.69 (95% CI, 0.65-0.73), and 6-status model was 0.67 (95% CI, 0.63-0.71). Classifying IABP and percutaneous VAD as short-term MCS reduced the effect size by 54%.

Conclusions and Relevance

In this registry-based study of US heart transplant candidates, a continuous multivariable allocation score outperformed the 6-status system in rank ordering heart transplant candidates by medical urgency and may be useful for the medical urgency component of heart allocation.

Providing Diagnostic Pathology Services in Low and Middle-Income Countries

Diagnostic pathology services in low and middle-income countries are often hindered by lack of expertise, equipment, and reagents. However, there are also educational, cultural, and political decisions, which must be addressed in order to provide these services successfully. In this review, we describe some of the infrastructure barriers that must be overcome and provide 3 examples of implementing molecular testing in Rwanda and Honduras despite initial lack of resources.

Accuracy-based proficiency testing for estradiol measurements

OBJECTIVES

Accuracy of estradiol measurements is important but conventional proficiency testing (PT) cannot assess accuracy when possibly non-commutable samples are used and method peer-group means are the targets. Accuracy-based assessment of estradiol measurements is needed.

DESIGN AND METHODS

Five serum samples were prepared from single donors, frozen, and distributed overnight to 76 New York State Department of Health (NYSDOH)-certified laboratories. Participants analyzed samples for estradiol. The biases of group means were assessed against the Centers for Disease Control and Prevention (CDC)-defined targets, evaluated using the Hormone Standardization Program (HoSt) E2 performance criterion of ±12.5 %. Each laboratory's performance was evaluated using total allowable error (acceptance limits) of target ±25 % or ±15 pg/mL (55 pmol/L) (whichever was greater, NYSDOH), target ±30 % (Clinical Laboratory Improvement Amendments [CLIA]), and target ±26 % (minimal limit based on biological variation [BV]).

RESULTS

The biases (range) were 34 % (-17 % to 175 %), 40 % (-33 % to 386 %), 16 % (-45 % to 193 %), 5 % (-27 % to 117 %), and -4% (-31 % to 21 %), for samples at estradiol of 24.1, 28.4, 61.7, 94.1, and 127 pg/mL, or 89, 104, 227, 345, and 466 pmol/L, respectively. Large positive method/analytical systematic biases were revealed for 9 commonly used method/analytical systems in the United States at low estradiol concentrations. Of the 9 analytical systems, 0, 0, 3, 7 and 6 met the HoSt criterion for the samples with estradiol at the five respective concentrations. PT evaluation showed that 59 %, 69 % and 87 % of laboratories would receive a PT event passing (satisfactory) score when the CDC-defined target and a criterion of NYSDOH, CLIA or BV was used, respectively. However, >95 % laboratories would obtain PT passing score if method peer-group means were used as targets regardless of the criterion used.

CONCLUSIONS

Improvement in accuracy of estradiol measurements is needed, particularly at low estradiol concentrations. Accuracy-based PT provides unambiguous information about the accuracy of methods/analytical systems.

Architecture of the Mass Spectrometry Data Management Pipeline in the SMART-CARE Project

In the SMART-CARE project- a systems medicine approach to stratification of cancer recurrence in Heidelberg, Germany - a streamlined mass-spectrometry (MS) workflow for identification of cancer relapse was developed. This project has multiple partners from clinics, laboratories and computational teams. For optimal collaboration, consistent documentation and centralized storage, the linked data repository was designed. Clinical, laboratory and computational group members interact with this platform and store meta- and raw-data. The specific architectural choices, such as pseudonymization service, uploading process and other technical specifications as well as lessons learned are presented in this work. Altogether, relevant information in order to provide other research groups with a head-start for tackling MS data management in the context of systems medicine research projects is described.

Performance Evaluation of the Commonly-Used Portable Cholesterol Sensors for Telehealth Services in the Unreached Communities

Portable medical sensors play an important role in healthcare services, especially in rural communities. Many telehealth systems use these devices for providing patients' vital information from a distance to remote doctors. Erroneous data will not only mislead the remote doctor for correct diagnosis but it will cause health threats to these unreached community people. Therefore, it is very important to identify good sensors with an acceptable level of accuracy but within the affordable price of the available sensors in the market. This study aims to identify quality portable cholesterol sensors with high accuracy with the reference of the Japanese clinical pathology laboratory as a gold standard. We have considered cholesterol sensors that measure total cholesterol for this study that are commonly used in the developing countries of Asia. We found that out of four, three of them were very much erroneous and cannot be recommended even for primary healthcare.

Anatomic and clinical pathology services and infrastructure in Zambia

OBJECTIVES

Pathology services are limited across most of sub-Saharan Africa. We sought to ascertain the availability of anatomic and clinical pathology services and diagnostic resources in Zambia.

METHODS

Two individual surveys-one for anatomic pathology and one for clinical pathology/laboratory medicine-were developed by subject matter experts. These surveys were administered to individuals involved in pathology and laboratory medicine diagnostic services at hospitals and laboratories across Zambia from May to October 2022 using the American Society for Clinical Pathology email listserv.

RESULTS

A total of 20 responses were received from 17 unique laboratories-8 sites provide anatomic pathology (AP) services, 12 provide clinical pathology (CP) services, and 3 perform both AP and CP services. Anatomic pathology services are variable and generally limited to a few of the responding laboratories, as only 1 laboratory performs immunohistochemical staining on surgical pathology specimens, and only 2 perform general histochemical stains. Conversely, certain microbiology testing (eg, for HIV) is more widely available.

CONCLUSIONS

This study of 17 unique laboratories represents the most complete analysis of pathology capabilities in Zambia. Despite initiatives to improve pathology services, both personnel and infrastructure challenges remain. Given a population of approximately 20 million, expansion of anatomic pathology in Zambia must be prioritized.

Screening for Colorectal Cancer: The Role of Clinical Laboratories

BACKGROUND

Colorectal cancer (CRC) is a leading cause of cancer incidence and mortality. Screening can result in reductions in incidence and mortality, but there are many challenges to uptake and follow-up.

CONTENT

Here, we will review the changing epidemiology of CRC, including increasing trends for early and later onset CRC; evidence to support current and emerging screening strategies, including noninvasive stool and blood-based tests; key challenges to ensuring uptake and high-quality screening; and the critical role that clinical laboratories can have in supporting health system and public health efforts to reduce the burden of CRC on the population.

SUMMARY

Clinical laboratories have the opportunity to play a seminal role in optimizing early detection and prevention of CRC.

Technical Note: Comparison of Alinity c Hemoglobin A1c Immunoassay with Premier Hb9210 Automated HPLC Assay: A Preliminary Report

OBJECTIVE

We utilized Premier Hb9210 analyzer (HPLC method; Trinity Biotech, Jamestown, NY) for measuring HBA1c in whole blood. As our laboratory is transitioning to Abbott system, we compared HbA1c values obtained by Alinity c and Premier Hb9210.

METHODS

The Premier Hb9210 analyzer is based on boronate affinity high performance liquid chromatography with analytical measurement range of 3.8 to 18.5%. The Alinity c Hemoglobin A1c assay measured both total hemoglobin and HbA1c (enzymatic assay) in whole blood and then calculated %HbA1c. The analytical measurement range of this assay is 4 to 14% of HbA1c. We evaluated the analytical performance of Alinity c HbA1c by evaluating precision and also comparing 77 clinical samples with our reference HPLC method.

RESULTS

Both Alinity c HbA1c and Premier HB9210 have excellent total precision. Plotting HbA1c results obtained by the Premier Hb9210 analyzer in the x-axis (currently used reference method) and the corresponding values obtained by the Alinity c assay, we observed the following regression equation: y=0.9473x+0.1548 ( n=77, r=0.99).

DISCUSSION

Our result indicates that HbA1c enzymatic assay on the Alinity c analyzer showed values comparable to HPLC method. However, at the decision points (2.8% average negative bias at >6.4% and 3.3% average negative bias at 7%), HbA1c values obtained by the Alinity c analyzer were lower than the reference method.

CONCLUSIONS

We conclude that HbA1c assay on the Alinity c analyzer is a viable alternative to HPLC for measuring HbA1c in clinical laboratories but values at the decision points must be interpreted with caution and if necessary should be repeated by a reference HPLC method.

The LEAP checklist for laboratory evaluation and analytical performance characteristics reporting of clinical measurement procedures

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

Contrastive Transfer Learning for Prediction of Adverse Events in Hospitalized Patients

OBJECTIVE

Deterioration index (DI) is a computer-generated score at a specific frequency that represents the overall condition of hospitalized patients using a variety of clinical, laboratory and physiologic data. In this paper, a contrastive transfer learning method is proposed and validated for early prediction of adverse events in hospitalized patients using DI scores.

METHODS AND PROCEDURES

An unsupervised contrastive learning (CL) model with a classifier is proposed to predict adverse outcome using a single temporal variable (DI scores). The model is pretrained on an unsupervised fashion with large-scale time series data and fine-tuned with retrospective DI score data.

RESULTS

The performance of this model is compared with supervised deep learning models for time series classification. Results show that unsupervised contrastive transfer learning with a classifier outperforms supervised deep learning solutions. Pretraining of the proposed CL model with large-scale time series data and fine-tuning that with DI scores can enhance prediction accuracy.

CONCLUSION

A relationship exists between longitudinal DI scores of a patient and the corresponding outcome. DI scores and contrastive transfer learning can be used to predict and prevent adverse outcomes in hospitalized patients.

CLINICAL IMPACT

This paper successfully developed an unsupervised contrastive transfer learning algorithm for prediction of adverse events in hospitalized patients. The proposed model can be deployed in hospitals as an early warning system for preemptive intervention in hospitalized patients, which can mitigate the likelihood of adverse outcomes.

Recommendations for Setting a Criterion and Assessing Commutability of Sample Materials Used in External Quality Assessment/Proficiency Testing Schemes

It is important for external quality assessment materials (EQAMs) to be commutable with clinical samples; i.e., they should behave like clinical samples when measured using end-user clinical laboratory in vitro diagnostic medical devices (IVD-MDs). Using commutable EQAMs makes it possible to evaluate metrological traceability and/or equivalence of results between IVD-MDs. The criterion for assessing commutability of an EQAM between 2 IVD-MDs is that its result should be within the prediction interval limits based on the statistical distribution of the clinical sample results from the 2 IVD-MDs being compared. The width of the prediction interval is, among other things, dependent on the analytical performance characteristics of the IVD-MDs. A presupposition for using this criterion is that the differences in nonselectivity between the 2 IVD-MDs being compared are acceptable. An acceptable difference in nonselectivity should be small relative to the analytical performance specifications used in the external quality assessment scheme. The acceptable difference in nonselectivity is used to modify the prediction interval criterion for commutability assessment. The present report provides recommendations on how to establish a criterion for acceptable commutability for EQAMS, establish the difference in nonselectivity that can be accepted between IVD-MDs, and perform a commutability assessment. The report also contains examples for performing a commutability assessment of EQAMs.

High prevalence group testing in epidemiology with geometrically inspired algorithms

Demand for mass surveillance during peak times of the SARS-CoV-2 pandemic caused high workload for clinical laboratories. Efficient and cost conserving testing designs by means of group testing can substantially reduce resources during possible future emergency situations. The novel hypercube algorithm proposed by Mutesa et al. 2021 published in Nature provides methodological proof of concept and points out the applicability to epidemiological testing. In this work, the algorithm is explored and expanded for settings with high group prevalence. Numerical studies investigate the limits of the adapted hypercube methodology, allowing to optimize pooling designs for specific requirements (i.e. number of samples and group prevalence). Hyperparameter optimization is performed to maximize test-reduction. Standard deviation is examined to investigate resilience and precision. Moreover, empirical validation was performed by elaborately pooling SARS-CoV-2 virus samples according to numerically optimized pooling designs. Laboratory experiments with SARS-CoV-2 sample groups, ranging from 50 to 200 items, characterized by group prevalence up to 10%, are successfully processed and analysed. Test-reductions from 50 to 72.5% were achieved in the experimental setups when compared to individual testing. Higher theoretical test-reduction is possible, depending on the number of samples and the group prevalence, indicated by simulation results.

AI Chatbots in Clinical Laboratory Medicine: Foundations and Trends

BACKGROUND

Artificial intelligence (AI) conversational agents, or chatbots, are computer programs designed to simulate human conversations using natural language processing. They offer diverse functions and applications across an expanding range of healthcare domains. However, their roles in laboratory medicine remain unclear, as their accuracy, repeatability, and ability to interpret complex laboratory data have yet to be rigorously evaluated.

CONTENT

This review provides an overview of the history of chatbots, two major chatbot development approaches, and their respective advantages and limitations. We discuss the capabilities and potential applications of chatbots in healthcare, focusing on the laboratory medicine field. Recent evaluations of chatbot performance are presented, with a special emphasis on large language models such as the Chat Generative Pre-trained Transformer in response to laboratory medicine questions across different categories, such as medical knowledge, laboratory operations, regulations, and interpretation of laboratory results as related to clinical context. We analyze the causes of chatbots' limitations and suggest research directions for developing more accurate, reliable, and manageable chatbots for applications in laboratory medicine.

SUMMARY

Chatbots, which are rapidly evolving AI applications, hold tremendous potential to improve medical education, provide timely responses to clinical inquiries concerning laboratory tests, assist in interpreting laboratory results, and facilitate communication among patients, physicians, and laboratorians. Nevertheless, users should be vigilant of existing chatbots' limitations, such as misinformation, inconsistencies, and lack of human-like reasoning abilities. To be effectively used in laboratory medicine, chatbots must undergo extensive training on rigorously validated medical knowledge and be thoroughly evaluated against standard clinical practice.

The LEAP checklist for Laboratory Evaluation and Analytical Performance characteristics reporting of clinical measurement procedures

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

The LEAP checklist for Laboratory Evaluation and Analytical Performance Characteristics reporting of clinical measurement procedures

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript.The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

Design of an algorithm for the detection of intravenous fluid contamination in clinical laboratory samples

OBJECTIVES

Contamination of blood samples from patients receiving intravenous fluids is a common error with potential risk to the patient. Algorithms based on the presence of aberrant results have been described but have the limitation that not all infusion fluids have the same composition. Our objective is to develop an algorithm based on the detection of the dilution observed on the analytes not usually included in infusion fluids.

METHODS

A group of 89 cases was selected from samples flagged as contaminated. Contamination was confirmed by reviewing the clinical history and comparing the results with previous and subsequent samples. A control group with similar characteristics was selected. Eleven common biochemical parameters not usually included in infusion fluids and with low intraindividual variability were selected. The dilution in relation to the immediate previous results was calculated for each analyte and a global indicator, defined as the percentage of analytes with significant dilution, was calculated. ROC curves were used to define the cut-off points.

RESULTS

A cut-off point of 20 % of dilutional effect requiring also a 60 % dilutional ratio achieved a high specificity (95 % CI 91-98 %) with an adequate sensitivity (64 % CI 54-74 %). The Area Under Curve obtained was 0.867 (95 % CI 0.819-0.915).

CONCLUSIONS

Our algorithm based on the global dilutional effect presents a similar sensitivity but greater specificity than the systems based on alarming results. The implementation of this algorithm in the laboratory information systems may facilitate the automated detection of contaminated samples.

A head-to-head comparison of three MALDI-TOF mass spectrometry systems with 16S rRNA gene sequencing

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has revolutionized diagnostics in culture-based microbiology. Commonly used MALDI-TOF MS systems in clinical microbiology laboratories are MALDI Biotyper (Bruker Daltonics) and Vitek MS (bioMérieux), but recently the new EXS2600 (Zybio) has been launched. This study aimed to evaluate the performance of the three devices by comparing the results to 16S rRNA gene sequencing. A set of 356 previously collected difficult-to-identify bacteria was tested in parallel with the three systems. Only the direct smear method and simple formic acid extraction were applied. Valid results were achieved for 98.6%, 94.4%, and 93.3% of all isolates by MALDI Biotyper, EXS2600, and Vitek MS, respectively. Of all valid results, agreement with sequencing data was achieved in 98.9%, 98.5%, and 99.7% by MALDI Biotyper, EXS2600, and Vitek MS, respectively. Considering only the isolates with valid measurements at the single-species level, misidentification rates were 0%, 2.6%, and 1.1% for MALDI Biotyper, EXS2600, and Vitek MS, respectively. Apart from minor performance differences, our data demonstrate that the three systems provide comparable results and are suitable for use in medical diagnostic laboratories.

Reference intervals of biochemical analytes in healthy adults from northern China: A population-based cross-sectional study

Reference intervals (RIs) of laboratory testing play a fundamental role in medical activities. RIs vary greatly for populations in different areas This study aimed to evaluate the age- and sex-specific reference intervals for a healthy population in a typical city of northern China. A cross-sectional study was performed in 4 tertiary care centers of Shijiazhuang of China, biochemical analytes were analyzed using a Beckman Coulter AU5800 (Beckman Coulter Inc., Brea, CA). A total of 42,979 healthy individuals were involved in this study. Grouped by age- and sex-specific, reference intervals of all the measures have been established. We found that different age groups of males and females have significant differences (all P < .001) in levels of various biochemical analytes. We provided a comprehensive age- and sex-specific RIs for biochemical analytes, which showed dynamic changes with both age and sex. For the local population, the reference intervals established here can be adopted in other clinical laboratories after appropriate validation.

The LEAP checklist for laboratory evaluation and analytical performance characteristics reporting of clinical measurement procedures

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the Laboratory Evaluation and Analytical Performance Characteristics (LEAP) checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

veRification: an R Shiny application for laboratory method verification and validation

OBJECTIVES

According to international standards, clinical laboratories are required to verify the performance of assays prior to their implementation in routine practice. This typically involves the assessment of the assay's imprecision and trueness vs. appropriate targets. The analysis of these data is typically performed using frequentist statistical methods and often requires the use of closed source, proprietary software. The motivation for this paper was therefore to develop an open-source, freely available software capable of performing Bayesian analysis of verification data.

METHODS

The veRification application presented here was developed with the freely available R statistical computing environment, using the Shiny application framework. The codebase is fully open-source and is available as an R package on GitHub.

RESULTS

The developed application allows the user to analyze imprecision, trueness against external quality assurance, trueness against reference material, method comparison, and diagnostic performance data within a fully Bayesian framework (with frequentist methods also being available for some analyses).

CONCLUSIONS

Bayesian methods can have a steep learning curve and thus the work presented here aims to make Bayesian analyses of clinical laboratory data more accessible. Moreover, the development of the application and seeks to encourage the dissemination of open-source software within the community and provides a framework through which Shiny applications can be developed, shared, and iterated upon.

A Review of Current Practices and Future Trends in Body Fluid Testing

BACKGROUND

Body fluid testing in the clinical chemistry laboratory is a cornerstone in the diagnostic workup of pathological effusions. Laboratorians may not be aware of the preanalytical workflows used in the collection of body fluids though the value is evident whenever processes change or issues arise. The analytical validation requirements can vary depending on the regulations dictated by the laboratories' jurisdiction and accreditor requirements. Much of analytical validation hinges on how useful testing is to clinical care. Usefulness of testing varies with how well established and incorporated the tests and interpretation are in practice guidelines.

CONTENT

Body fluid collections are depicted and described so clinical laboratorians have a basic appreciation of what specimens are submitted to the laboratory for testing. A review of validation requirements by major laboratory accreditation entities is presented. A review of the usefulness and proposed decision limits for common body fluid chemistry analytes is presented. Body fluid tests that show promise and those that are losing (or lost long ago) value are also reviewed.

SUMMARY

The total testing process from collection to result interpretation can be complicated and easily overlooked by the clinical laboratory. This review aims to improve the understanding and awareness of collections, validation, result interpretation, and provide an update on recent trends.

The Future of Laboratory-Developed Tests in Hemostasis Laboratories

Laboratory-developed tests (LDTs) are widely used in clinical hemostasis laboratories. The extent to which LDTs are regulated varies greatly around the world, and proposed changes to regulations have raised concerns about the future of LDTs in clinical laboratories. It is increasingly difficult to justify the use of an LDT where a commercially available method with regulatory approval is available. Conversely, where there is no suitable test with regulatory approval and there is a compelling clinical need, using an LDT outweighs the risk associated with not performing the test. We argue that LDTs are still required in specialist clinical laboratories to fulfill unmet clinical needs, and in lower middle-income countries where they are a vital resource.

Current status and challenges in establishing reference intervals based on real-world data

Reference intervals (RIs) are the cornerstone for evaluation of test results in clinical practice and are invaluable in judging patient health and making clinical decisions. Establishing RIs based on clinical laboratory data is a branch of real-world data mining research. Compared to the traditional direct method, this indirect approach is highly practical, widely applicable, and low-cost. Improving the accuracy of RIs requires not only the collection of sufficient data and the use of correct statistical methods, but also proper stratification of heterogeneous subpopulations. This includes the establishment of age-specific RIs and taking into account other characteristics of reference individuals. Although there are many studies on establishing RIs by indirect methods, it is still very difficult for laboratories to select appropriate statistical methods due to the lack of formal guidelines. This review describes the application of real-world data and an approach for establishing indirect reference intervals (iRIs). We summarize the processes for establishing iRIs using real-world data and analyze the principle and applicable scope of the indirect method model in detail. Moreover, we compare different methods for constructing growth curves to establish age-specific RIs, in hopes of providing laboratories with a reference for establishing specific iRIs and giving new insight into clinical laboratory RI research. (201 words).

Patient-based pre-classified real-time quality control (PCRTQC)

BACKGROUND

Patient-based real-time quality control (PBRTQC) has gained increasing attention in clinical laboratory management. Although its valuable characteristics complement traditional quality control measures, its performance and practical application have faced scrutiny. In this study, patient-based pre-classified real-time quality control (PCRTQC), an extended approach was devised to enhance real-time quality control protocols.

METHODS

PCRTQC distinguishes itself by incorporating an additional patient pre-classification step utilising the OPTICS algorithm, thus addressing interference from diverse patient types. The complete set of patient test results obtained from a clinical chemistry analyser at The First Hospital of China Medical University in 2021 was utilised. Constant error (CE) and proportional error (PE) were introduced as analytical errors. Four analytes were selected to evaluate the PCRTQC, measuring probability for false rejection (Pfr) and the average number of patient samples until error detection (ANPed). Relevant error detection charts were generated.

RESULTS

The PCRTQC outperformed regression-adjusted real-time quality control (RARTQC) based on the ANPed by approximately 50% for both the CE and PE, compared to the RARTQC, particularly for the total allowable error threshold.

CONCLUSION

The pre-classification step effectively reduced inter-individual variation and improved data preprocessing, filtering, and modelling. The PCRTQC is a robust framework for real-time quality control research.