Quality indicators in laboratory medicine: state-of-the-art, quality specifications and future strategies

In the last few decades, quality in laboratory medicine has evolved in concert with the transformation and the changes (technological, scientific and organizational) in this sector. Laboratory professionals have faced great challenges, at times being overwhelmed, yet also involved in this progress. Worldwide, laboratory professionals and scientific societies involved in laboratory medicine have raised awareness concerning the need to identify new quality assurance tools that are effective in reducing the error rate and enhancing patient safety, in addition to Internal Quality Control (IQC) procedures and the participation in the External Quality Assessment Schemes (EQAS). The use of Quality Indicators (QIs), specifically designed for laboratory medicine are effective in assessing and monitoring all critical events occurring in the different phases of Total Testing Process (TTP), in particular, in the extra-analytical phases. The Model of Quality Indicators (MQI), proposed by the Working Group "Laboratory Errors and Patient Safety" (WG-LEPS) of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and validated by experts in consensus conferences, is an important window of opportunity for the medical laboratory to demonstrate the use of an effective quality assurance tool fit for this purpose. Aim of this paper is to provide an update of the state-of-the-art concerning the most used QIs data collected in 2021 and the Quality Specifications (QSs) proposed for their evaluation. Moreover, a strategy for the future is proposed in order to improve the MQI and encourage its use in medical laboratories throughout the world.

How to Really Understand and Improve the System of Internal Quality Control and External Quality Assessment in the Accreditation Process of the Medical Laboratory?

Internal quality control (IQC) regarding process to monitor analytical stability has a long tradition in laboratory medicine. The satisfactory results with different quality specifications of the IQC ensure the acceptability of the examination results. Although the statistical IQC is satisfactory some problems exist, resulting in unreliable patients' results due several reasons (non-commutable control materials, lot to lot difference of reagents, false interpreting test results regarding autovalidation or autoverification, different analytical and clinical specifications or goals etc.). Therefore, the results and findings of IQC have to be connected with external quality assessment (EQA) in order to provide the system of measurement of uncertainty (MU) with correct interpretation of laboratory result and detection relevant and significant shifts and drifts in medical laboratory.

Analysis and evaluation of the external quality assessment results of quality indicators in laboratory medicine all over China from 2015 to 2018

Background This study aimed to comprehensively evaluate laboratory quality in China and explore factors affecting laboratory errors through analyzing the external quality assessment (EQA) results of quality indicators (QIs). Methods According to model 3 (interpretive) of the proficiency testing scheme, the National Center for Clinical Laboratories of China (CNCCL) developed a questionnaire for 15 QIs. Clinical laboratories from different provinces of China participated in the EQA program of QIs annually and submitted data via an online reporting system named Clinet-EQA. The results of QIs were expressed in percentage and sigma value or minute. Three levels of quality specifications (QSs) were defined based on percentile values. Furthermore, the QIs were analyzed by disciplines, hospital scales and information construction levels of participant laboratories. Results A total of 3450 laboratories nationwide continuously attended the EQA program and submitted complete data from 2015 to 2018. The performance of most QIs has improved year by year. QIs in post-analytical gained the best performance with sigma values that varied from 5.3σ to 6.0σ. The comparison of results among different disciplines showed significant differences for five QIs. More than half of QIs had statistical differences among different hospital scales measured by hospital grades and number of hospital beds. The performance of nine QIs were influenced by information construction levels of participant laboratories. Conclusions The overall laboratory quality in China has improved since the initiation of EQA program for QIs, but the performance of some QIs was still unsatisfactory. Therefore, laboratories should make efforts for continuous quality improvement based on information provided by QSs.

Study of the analytical performance at different concentrations of hematological parameters using Spanish EQAS data

Background External quality assessment programs are one of the currently available tools to evaluate the analytical performance of clinical laboratories, where the measurement error (ME) obtained can be compared with quality specifications to evaluate possible deviations. The objective of this work was to analyze the ME behavior over the analytical range to assess the need to establish concentration-dependent specifications. Methods A total of 389,000 results from 585 laboratories and 2628 analyzers were collected from the Spanish external quality assessment schemes (EQAS) in hematology during the years 2015-2016. The parameters evaluated included white blood cells, red blood cells, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, platelets, prothrombin time, activated partial thromboplastin time, neutrophils, lymphocytes, monocytes, eosinophils, basophils, reticulocytes, hemoglobin A2, antithrombin, factor VIII, protein C and von Willebrand factor. The 90th percentile of ME was calculated for every concentration evaluated of each parameter. Results We found a significant variation in the analytical performance of leukocytes, platelets, neutrophils, lymphocytes, monocytes, eosinophils, basophils, prothrombin time, reticulocytes, hemoglobin A2, antithrombin and protein C. Furthermore, this ME variation may not allow complying with the same biological variability requirements within the whole analytical range studied. Conclusions Our work shows the importance of implementing concentration-dependent specifications which can help laboratories to use proper criteria for quality specifications selection and for a better external quality control results evaluation.

National surveys on 15 quality indicators for the total testing process in clinical laboratories of China from 2015 to 2017

Background As effective quality management tools, quality indicators (QIs) are widely used in laboratory medicine. This study aimed to analyze the results of QIs, identify errors and provide quality specifications (QSs) based on the state-of-the-art. Methods Clinical laboratories all over China participated in the QIs survey organized by the National Health Commission of People' Republic of China from 2015 to 2017. Most of these QIs were selected from a common model of QIs (MQI) established by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). All participants were asked to submit general information and original QIs data through a medical quality control data collection system. The results of QIs were reported in percentages and sigma, except turnaround time (TAT) which was measured in minutes. The 25th, 50th and 75th percentiles were, respectively, calculated as three levels of QSs, which were defined starting from the model proposed during the 1st Strategic Conference of the EFLM on "Defining analytical performance 15 years after the Stockholm Conference on Quality Specification in Laboratory Medicine". Results A total of 76 clinical laboratories from 25 provinces in China continuously participated in this survey and submitted complete data for all QIs from 2015 to 2017. In general, the performance of all reported QIs have improved or at least kept stable over time. Defect percentages of blood culture contamination were the largest in the pre-analytical phase. Intra-laboratory TAT was always larger than pre-examination TAT. Percentage of tests covered by inter-laboratory comparison was relatively low than others in the intra-analytical phase. The performances of critical values notification and timely critical values notification were the best with 6.0σ. The median sigma level of incorrect laboratory reports varied from 5.5σ to 5.7σ. Conclusions QSs of QIs provide useful guidance for laboratories to improve testing quality. Laboratories should take continuous quality improvement measures in all phases of total testing process to ensure safe and effective tests.

Validation of a Cell Proliferation Assay to Assess the Potency of a Dialyzable Leukocyte Extract Intended for Batch Release

Transferon^® is a blood product with immunomodulatory properties constituted by a complex mixture of peptides obtained from a human dialyzable leukocyte extract (DLE). Due to its complex nature, it is necessary to demonstrate batch consistency in its biological activity. Potency is the quantitative measure of biological activity and is also a quality attribute of drugs. Here we developed and validated a proliferation assay using Jurkat cells exposed to azathioprine, which is intended to determine the potency of Transferon^® according to international guidelines for pharmaceuticals. The assay showed a linear response (2.5 to 40 µg/mL), coefficients of variation from 0.7 to 13.6% demonstrated that the method is precise, while r² = 0.97 between the nominal and measured values obtained from dilutional linearity showed that the method is accurate. We also demonstrated that the cell proliferation response was specific for Transferon^® and was not induced by its vehicle nor by other peptide complex mixtures (glatiramer acetate or hydrolyzed collagen). The bioassay validated here was used to assess the relative potency of eight released batches of Transferon^® with respect to a reference standard, showing consistent results. The collective information from the validation and the assessment of several batches indicate that the bioassay is suitable for the release of Transferon^®.

The Importance of Quality Specifications in Safety Assessments of Amino Acids: The Cases of l-Tryptophan and l-Citrulline

The increasing consumption of amino acids from a wide variety of sources, including dietary supplements, natural health products, medical foods, infant formulas, athletic and work-out products, herbal medicines, and other national and international categories of nutritional and functional food products, increases the exposure to amino acids to amounts far beyond those normally obtained from the diet, thereby necessitating appropriate and robust safety assessments of these ingredients. Safety assessments of amino acids, similar to all food constituents, largely rely on the establishment of an upper limit [Tolerable Upper Intake Level (UL)] considered to be a guide for avoiding high intake, above which adverse or toxic effects might occur. However, reliable ULs have been difficult or impossible to define for amino acids because of inadequate toxicity studies in animals and scarce or missing clinical data, as well as a paucity or absence of adverse event reporting data. This review examines 2 amino acids that have been associated with in-market adverse events to show how quality specifications might have helped prevent the adverse clinical outcomes. We further highlight the importance of various factors that should be incorporated into an overall safety assessment of these and other amino acids. In addition to the traditional reliance on the established UL, well-defined quality specifications, review of synthesis and production strategies, potential interactions with drugs, contraindications with certain disease states, and cautionary use within certain age groups should all be taken into consideration.

Pre and Post Examination Aspects

After a long-standing tradition of analytical quality and analytical quality control programs, most medical laboratories that are aware of the need for total quality management, are experiencing new systems designed to assure quality throughout the entire total testing process, from the pre-analytical to the post-analytical steps. The availability of a new International Standard, ISO 15189:2003, specifically developed and designed to satisfy the requirements for quality management and competence in medical laboratories, should promote the harmonization of accreditation programs at an international level, and implementation of an effective quality system at a local level. The importance of the pre- and post-analytical phases are well recognized in the new International Standard and, therefore, efforts to comply with this standard might assure an approach that safeguards and continuously improves total quality in medical laboratories.