Deep learning-based automatic contour quality assurance for auto-segmented abdominal MR-Linac contours.

Objective.Deep-learning auto-segmentation (DLAS) aims to streamline contouring in clinical settings. Nevertheless, achieving clinical acceptance of DLAS remains a hurdle in abdominal MRI, hindering the implementation of efficient clinical workflows for MR-guided online adaptive radiotherapy (MRgOART). Integrating automated contour quality assurance (ACQA) with automatic contour correction (ACC) techniques could optimize the performance of ACC by concentrating on inaccurate contours. Furthermore, ACQA can facilitate the contour selection process from various DLAS tools and/or deformable contour propagation from a prior treatment session. Here, we present the performance of novel DL-based 3D ACQA models for evaluating DLAS contours acquired during MRgOART.Approach.The ACQA model, based on a 3D convolutional neural network (CNN), was trained using pancreas and duodenum contours obtained from a research DLAS tool on abdominal MRIs acquired from a 1.5 T MR-Linac. The training dataset contained abdominal MR images, DL contours, and their corresponding quality ratings, from 103 datasets. The quality of DLAS contours was determined using an in-house contour classification tool, which categorizes contours as acceptable or edit-required based on the expected editing effort. The performance of the 3D ACQA model was evaluated using an independent dataset of 34 abdominal MRIs, utilizing confusion matrices for true and predicted classes.Main results.The ACQA predicted 'acceptable' and 'edit-required' contours at 72.2% (91/126) and 83.6% (726/868) accuracy for pancreas, and at 71.2% (79/111) and 89.6% (772/862) for duodenum contours, respectively. The model successfully identified false positive (extra) and false negative (missing) DLAS contours at 93.75% (15/16) and %99.7 (438/439) accuracy for pancreas, and at 95% (57/60) and 98.9% (91/99) for duodenum, respectively.Significance.We developed 3D-ACQA models capable of quickly evaluating the quality of DLAS pancreas and duodenum contours on abdominal MRI. These models can be integrated into clinical workflow, facilitating efficient and consistent contour evaluation process in MRgOART for abdominal malignancies.

Assessing suitability and stability of materials for a head and neck anthropomorphic multimodality (MRI/CT) phantoms for radiotherapy.

OBJECTIVE: This study aims to identify and evaluate suitable and stable materials for developing a head and neck anthropomorphic multimodality phantom for radiotherapy purposes. These materials must mimic human head and neck tissues in both computed tomography (CT) and magnetic resonance imaging (MRI) and maintain stable imaging properties over time and after radiation exposure, including the high levels associated with linear accelerator (linac) use. Approach: Various materials were assessed by measuring their CT numbers and T1 and T2 relaxation times. These measurements were compared to literature values to determine how closely the properties of the candidate materials resemble those of human tissues in the head and neck region. The stability of these properties was evaluated monthly over a year and after radiation exposure to doses up to 1000 Gy. Statistical analyses were conducted to identify any significant changes over time and after radiation exposure. Main Results: 10% and 12.6% Polyvinyl alcohol cryogel (PVA-c) both exhibited T1 and T2 relaxation times and CT numbers within the range appropriate for brain grey matter. 14.3% PVA-c and some plastic-based materials matched the MRI properties of brain white matter, with CT numbers close to the clinical range. Additionally, some plastic-based materials showed T1 and T2 relaxation times consistent with MRI properties of fat, although their CT numbers were not suitable. Over time and after irradiation, 10% PVA-c maintained consistent properties for brain grey matter. 12.6% PVA-c's T1 relaxation time decreased beyond the range after the first month. Significance: This study identified 10% PVA-c as a substitute for brain grey matter, demonstrating stable imaging properties over a year and after radiation exposure up to 1000 Gy. However, the results highlight a need for further research to find additional materials to accurately simulate a wider range of human tissues. .

[Translated article] Medication reconciliation in hospitalized haematological patients.

OBJECTIVE: The main objective is to analyse unjustified discrepancies found during the medication reconciliation process in patients admitted to the Haematology Service of our hospital, in addition to the pharmaceutical interventions carried out. As a secondary objective, to detect possible points of the procedure to be perfected with a view to protocolizing the medication reconciliation process in haematological patients that adapts to the conditions of our center. METHODS: Cross-sectional observational pilot study carried out in a reference hospital in haematology for a population of 800 000 inhabitants. Adult inpatients admitted to the Haematology Service between August and October 2022 whose medication had been reconciled were included. The main variables were: number and type of unjustified discrepancy, proposed pharmaceutical intervention, and degree of acceptance. RESULTS: 36 conciliation processes were analysed, 34 admissions and 2 intrahospital transfer. 58.3% of the patients presented some unjustified discrepancy. 38 unjustified discrepancies were detected, with an acceptance of pharmaceutical interventions of 97.4%. The most common types of discrepancy were medication omission (56.8%) and drug interaction (24.3%). The most frequent pharmaceutical interventions were reintroducing medication (48.6%) and suspending treatment (16.2%). Polypharmacy and receiving chemotherapy treatment multiply by 4 the probability of presenting drug interactions. CONCLUSIONS: The most common unjustified discrepancies in the medication reconciliation process in hospitalized haematology patients are: medication omission and drug interactions. The reintroduction of medication and suspension of the prescription are the most frequent accepted pharmaceutical interventions. Polypharmacy is related to an increase in unjustified discrepancies. The factors that promote the appearance of interactions are admissions to receive chemotherapy treatment and polypharmacy. The main point of improvement detected is the need to create a circuit that allows conciliation to be carried out on discharge. Medication reconciliation contribute to improving patient safety by reducing medication errors.

A systems theory-based safety assessment of pre-treatment patient-specific quality assurance for intensity-modulated treatments in a single-vendor environment.

BACKGROUND AND PURPOSE: While patient-specific quality assurance (PSQA) has been integral to intensity-modulated treatments, its value is debated. A systems approach to safety is essential for understanding complex systems like radiation oncology but is often overlooked in PSQA research. This study aims to elucidate PSQA's fundamental value and identify opportunities for enhancing safety in intensity-modulated treatments. MATERIALS AND METHODS: First, causal scenarios that could lead to patient harm were identified using a prospective safety assessment technique developed for complex systems. Second, PSQA's ability to mitigate these scenarios was evaluated using standard stability and control principles. The analysis also included safeguards related to PSQA, such as daily linac QA, equipment commissioning, and equipment design. RESULTS: Ten causal scenarios were identified, highlighting well-known issues like flawed algorithms, data corruption, and hardware errors. Mitigation is achieved through advanced dose calculation and optimization algorithms, software and data integration, and preconfigured beam data, which improve decision-making and system state determination. Modern linac control systems enhance all aspects of system stability and control. Commissioning, daily linac QA, and PSQA are effective in enhancing the determination of system states only when feedback is non-overlapping and unambiguous. CONCLUSION: Given equipment improvement and related safeguards, the feedback generated from PSQA has diminished in value. To better complement other safeguards, PSQA should evolve to provide automated, unambiguous detection of any potential catastrophic treatment deviations prior to treatment. This evolution would allow physicists to focus on more critical aspects of patient care in radiation oncology.

Quality assurance applied to semen analysis.

Artificial insemination is an important biotechnology employed in livestock production. Production of semen products requires analysis of sperm concentration, motility and morphology. Although adequate analytical procedures are essential to ensure product quality, several multicenter studies have reported large variations in semen analysis results within and across laboratories. Differences in equipment and methodology, inconsistent training and performance testing, and lack of quality assurance programs are likely responsible for these observations. The somewhat pervasive perception that semen analysis is a trivial task must be challenged as it jeopardizes efficient semen production and germplasm utilization. This manuscript reviews the Quality Assurance (QA) procedures recommended to control results obtained during semen analysis. Reference, standard technical specifications for basic semen analysis are also described.

Accuracy of pelvic bone segmentation for 3d printing: a study of segmentation accuracy based on anatomic landmarks to evaluate the influence of the observer.

BACKGROUND: 3D printing has a wide range of applications and has brought significant change to many medical fields. However, ensuring quality assurance (QA) is essential for patient safety and requires a QA program that encompasses the entire production process. This process begins with imaging and continues on with segmentation, which is the conversion of Digital Imaging and Communications in Medicine (DICOM) data into virtual 3D-models. Since segmentation is highly influenced by manual intervention the influence of the users background on segmentation accuracy should be thoroughly investigated. METHODS: Seventeen computed tomography (CT) scans of the pelvis with physiological bony structures were identified, anonymized, exported as DICOM data sets, and pelvic bones were segmented by four observers with different backgrounds. Landmarks were measured on DICOM images and in the segmentations. Intraclass correlation coefficients (ICCs) were calculated to assess inter-observer agreement, and the trueness of the segmentation results was analyzed by comparing the DICOM landmark measurements with the measurements of the segmentation results. The correlation between segmentation trueness and segmentation time was analyzed. RESULTS: The lower limits of the 95% confidence intervals of the ICCs for the seven landmarks analyzed ranged from 0.511 to 0.986. The distance between the iliac crests showed the highest agreement between observers, while the distance between the ischial tuberosities showed the lowest. The distance between the upper edge of the symphysis and the promontory showed the lowest deviation between DICOM measurements and segmentation measurements (mean deviations < 1 mm), while the intertuberous distance showed the highest deviation (mean deviations 14.5-18.2 mm). CONCLUSIONS: Investigators with diverse backgrounds in segmentation and varying experience with slice images achieved pelvic bone segmentations with landmark measurements of mostly high agreement in a setup with high realism. In contrast, high variability was observed in the segmentation of the coccyx. In general, interobserver agreement was high, but due to measurement inaccuracies, landmark-based approaches cannot conclusively show that segmentation accuracy is within a clinically tolerable range of 2 mm for the pelvis. If the segmentation is performed by a very inexperienced user, the result should be reviewed critically by the clinician in charge.

Decreasing Social Media Use Through Motivational Interviewing: A Pediatric Primary Care Quality Improvement Project.

BACKGROUND: Social media use has been correlated to worsening anxiety and depression in teenagers. LOCAL PROBLEM: In the United Staes, social media is frequently used amongst adolescents, and rates of anxiety and depression in this population have increased over time. METHODS: A convenience sample of adolescents aged 12 to 18 years old were evaluated using a pre-post design. INTERVENTIONS: This quality improvement project introduced screen time assessment and motivational interviewing to decrease social media use and improve mental health among adolescents. RESULTS: PHQ-9 scores remained consistent throughout the project. There was an overall decrease in participant SCARED scores and social media use declined over the 12-week period. CONCLUSIONS: Results from this project suggest an opportunity for pediatric healthcare providers to standardize social media use screening in adolescent care and utilize motivational interviewing to promote adolescent wellbeing.

Evaluation of antenatal care quality for preterm birth prevention using an auditable scoring system: A retrospective, descriptive, longitudinal study in Sydney, Australia.

INTRODUCTION: Preterm birth continues to be one of the most significant contributors to perinatal death. This study aims to evaluate the quality of antenatal care provided to women delivering preterm. METHODS: This was a retrospective, descriptive, longitudinal review of all women who had antenatal care within a single Australian tertiary hospital and delivered spontaneously between 24 and 37 weeks of gestation, using an auditable scoring system assessing potential interventions for prevention of preterm birth. The review was limited to singleton pregnancies without fetal abnormalities delivering between January 2013 and April 2015. The audit tool was developed by reference to established 'best practice' guidance for prediction and prevention of preterm birth based on Royal Australian and New Zealand College of Obstetricians and Gynaecologists guidelines and published literature. Different pathways were assessed for women deemed either low- or high-risk at the outset of antenatal care. RESULTS: A series of 161 pregnancies that delivered preterm (between 24 and 37 weeks' gestation) were reviewed. The quality of antenatal care was scored 'good' in 42.9% and 50% of high-risk and low-risk women, respectively. Care was scored 'adequate', with room for improvement in 51.4% and 45.2% of the two corresponding groups. The main deficiencies in care were recorded evidence of assessment of cervical length (absent in 35% of cases) and failure to screen for bacterial vaginosis in high-risk women. CONCLUSIONS: Auditing antenatal care for prevention of preterm birth allows identification of suboptimal practice allowing service improvement and potential intervention for preterm birth prevention.

[Utilization of registers to create an evidence-based approach in catastrophes and civil defence]. / Nutzung von Registern zur Schaffung eines evidenzbasierten Vorgehens im Katastrophen- und Zivilschutzfall.

Medical data registers are a key instrument of medical care research and a valuable tool for medical quality assurance. The structured plausibility tested documentation of large case numbers on a longitudinally oriented time axis with different points in time of data acquisition enables statements to be made on numerous relevant outcomes, not only the mortality of patients. For incidents outside the daily routine care in trauma surgery, such as natural disasters, accidents with multiple casualties and nonmilitary treatment of the domestic population in defence situations, such registers can provide data-based recommendations for action. These data, mainly obtained from routine traumatological treatment, enable a targeted resource management in the abovenamed incidents, which are associated with mass casualties. Due to the utilization of registers from the military field or from international registers, the perspective is additionally extended with respect to treatment strategies and injury patterns. Whether data can also be generated in a suitable manner for the abovenamed registers in specific disaster situations and can provide a direct gain of knowledge from the incident, must be critically discussed. The maintenance of the register datasets is time-consuming and has been subjected to a more stringent regulation at least since May 2018, when the European Union General Data Protection Regulation (EU-GDPR) came into force. The future Register Act in Germany will hopefully achieve greater simplification in the documentation of routine data.

A broadly reactive ultralong bovine antibody that can determine the integrity of foot-and-mouth disease virus capsids.

Foot-and-mouth disease vaccination using inactivated virus is suboptimal, as the icosahedral viral capsids often disassemble into antigenically distinct pentameric units during long-term storage, or exposure to elevated temperature or lowered pH, and thus raise a response that is no longer protective. Furthermore, as foot-and-mouth disease virus (FMDV)'s seven serotypes are antigenically diverse, cross-protection from a single serotype vaccine is limited, and most existing mouse and bovine antibodies and camelid single-domain heavy chain-only antibodies are serotype-specific. For quality control purposes, there is a real need for pan-serotype antibodies that clearly distinguish between pentamer (12S) and protective intact FMDV capsid. To date, few cross-serotype bovine-derived antibodies have been reported in the literature. We identify a bovine antibody with an ultralong CDR-H3, Ab117, whose structural analysis reveals that it binds to a deep, hydrophobic pocket on the interior surface of the capsid via the CDR-H3. Main-chain and hydrophobic interactions provide broad serotype specificity. ELISA analysis confirms that Ab117 is a novel pan-serotype and conformational epitope-specific 12S reagent, suitable for assessing capsid integrity.

Enhancing exam question quality in medical education through bootstrapping.

Medical schools are required to assess and evaluate their curricula and to develop exam questions with strong reliability and validity evidence, often based on data derived from statistically small samples of medical students. Achieving a large enough sample to reliably and validly evaluate courses, assessments, and exam questions would require extensive data collection over many years, which is inefficient, especially in the fast-changing educational environment of medical schools. This article demonstrates how advanced quantitative methods, such as bootstrapping, can provide reliable data by resampling a single dataset to create many simulated samples. This economic approach, among others, allows for the creation of confidence intervals and, consequently, the accurate evaluation of exam questions as well as broader course and curriculum assessments. Bootstrapping offers a robust alternative to traditional methods, improving the psychometric quality of exam questions, and contributing to fair and valid assessments in medical education.

The EuroFlow PIDOT external quality assurance scheme: enhancing laboratory performance evaluation in immunophenotyping of rare lymphoid immunodeficiencies.

OBJECTIVES: The development of External Quality Assessment Schemes (EQAS) for clinical flow cytometry (FCM) is challenging in the context of rare (immunological) diseases. Here, we introduce a novel EQAS monitoring the primary immunodeficiency Orientation Tube (PIDOT), developed by EuroFlow, in both a 'wet' and 'dry' format. This EQAS provides feedback on the quality of individual laboratories (i.e., accuracy, reproducibility and result interpretation), while eliminating the need for sample distribution. METHODS: In the wet format, marker staining intensities (MedFIs) within landmark cell populations in PIDOT analysis performed on locally collected healthy control (HC) samples, were compared to EQAS targets. In the dry format, participants analyzed centrally distributed PIDOT flow cytometry data (n=10). RESULTS: We report the results of six EQAS rounds across 20 laboratories in 11 countries. The wet format (212 HC samples) demonstrated consistent technical performance among laboratories (median %rCV on MedFIs=34.5 %; average failure rate 17.3 %) and showed improvement upon repeated participation. The dry format demonstrated effective proficiency of participants in cell count enumeration (range %rCVs 3.1-7.1 % for the major lymphoid subsets), and in identifying lymphoid abnormalities (79.3 % alignment with reference). CONCLUSIONS: The PIDOT-EQAS allows laboratories, adhering to the standardized EuroFlow approach, to monitor interlaboratory variations without the need for sample distribution, and provides them educational support to recognize rare clinically relevant immunophenotypic patterns of primary immunodeficiencies (PID). This EQAS contributes to quality improvement of PID diagnostics and can serve as an example for future flow cytometry EQAS in the context of rare diseases.

Impact of hemodialysis center accreditation on patient mortality: Korean nationwide cohort study.

Background: Since hemodialysis (HD) patients are prone to various complications and high mortality, they need to be treated in HD units with professional personnel, proper equipment, and facilities. The Korean Society of Nephrology has been conducting an HD unit accreditation program since 2016. This study was performed to evaluate whether a qualified dialysis center (QDC) reduced the mortality of HD patients. Methods: This longitudinal, observational cohort study included 31,227 HD from 832 facilities. HD units were classified into two groups: the hospitals that have been certified as QDC between 2016 and 2018 (n = 219) and hospitals that have never been certified as QDC (non-QDC, n = 613). Baseline characteristics and patient mortality were compared between QDC vs. non-QDC groups using Korean HD quality assessment data from 2018. Multivariate logistic regression and the Cox proportional hazards model were used to compare patient mortality between the two groups. Results: Among study subjects, 30.6% of patients were treated at QDC and 69.4% were treated at non-QDC. The patients in the QDC were younger and had a longer dialysis duration, lower serum phosphorus and calcium levels, and higher hemoglobin and single-pool Kt/V levels compared to the patients from the non-QDC group. After adjusting for demographic and clinical parameters, QCD independently reduced mortality risk (hazard ratio, 0.897; 95% confidence interval, 0.847-0.950; p < 0.001). Conclusion: The HD unit accreditation program may reduce the risk of death among patients undergoing HD.

[Possibilities of the utilization of trauma networks of the German Society for Trauma Surgery using digital solutions]. / Möglichkeiten der Nutzung von TraumaNetzwerken DGU unter Verwendung von digitalen Lösungen.

This paper describes the use of digital solutions to improve the care of trauma patients in Germany. The focus is on the trauma networks of the German Society for Trauma Surgery (Deutsche Gesellschaft für Unfallchirurgie, DGU). The use of digital solutions includes quality assurance through the TraumaRegister, which enables comprehensive data analysis as well as preregistration and resource utilization through programs such as the interdisciplinary proof of treatment IVENA eHealth, Rescuetrack and Rescue-Net. In addition, Predictive Hospital Resource Planning is presented, which optimizes resource forecasting using artificial intelligence (AI). Telemedical services such as Medgate and teleradiology solutions (Nexus/Chili) offer additional support, especially in rural areas. The paper shows how the digitalization of medical care is crucial to improving the efficiency and quality of treatment of trauma patients. In addition, the paper shows possible developments in the field of clinical decision making through AI.

'Does this fecal microbiota transplant work?' Quality assurance of capsule based fecal microbiota transplant production.

BACKGROUND: Fecal Microbiota Transplant (FMT) is an effective treatment for recurring Clostridioides Difficile Infections (rCDI). FMT administered via oral capsules (caFMT) offers several practical advantages to conventional liquid FMT. We began using caFMT in 2021 imported from an external institution. Based on similar production methods, we began our own caFMT production in 2022. We aimed to evaluate the quality of our caFMT. STUDY DESIGN AND METHODS: We created a database of all FMT treatments (n = 180) provided by our institution. Quality of all FMT was evaluated by treatment success rates. We compared our caFMT to the imported caFMT. RESULTS: Our caFMT yielded similar success rates compared to that of the imported caFMT, 65% (CI 95% 58-72%) and 72% (CI 95% 66-79%) respectively. FMT administered via colonoscopy had a significantly higher success rate, 79% (CI 95% 73-85%) than own our caFMT and other routes of administration. The combined success rate of treatments increased notably for all routes of administration when repeating FMT after prior failure. DISCUSSION: The fact that our caFMT compared similarly to the imported caFMT was viewed as a success in terms of quality assurance. Our caFMT had a slightly lower success rates compared to data from other studies, but could be affected by several other factors than our FMT-production methods. A lower success rate of caFMT compared to FMT via colonoscopy is acceptable due to the practical advantages offed by caFMT. Our study serves as a practical example, proving that of the standardization of caFMT production is indeed viable.

Vaginal Uncomplicated Delivery Rate as a Quality Indicator Compared to Cesarean Delivery Rate: A Quantitative Analysis of a Population Database.

OBJECTIVE: The objective of this study is comparing the vaginal uncomplicated delivery (VUD) rate, defined as all vaginal deliveries (including forceps and vacuum) without an adverse maternal or neonatal labour outcome, to the cesarean delivery (CD) rate, as a performance indicator. METHODS: This is a retrospective cohort analysis from a provincial database of all term deliveries by an obstetrician in a single year, excluding diagnoses preventing active labour. Most obstetricians in this jurisdiction practice consultative obstetrics, focused on supporting primary maternity care. We investigated the association of adverse delivery (AD), measured by the adverse outcome index (AOI), with CD and VUD rates. RESULTS: We report 16 620 deliveries by 210 obstetricians, with a vaginal delivery rate of 39.6%, of which 36.6% were operative vaginal delivery. The overall AD rate was 9.9%, and the overall VUD rate was 34%. While the CD and VUD both correlated with mode of delivery, only the VUD rate was correlated to the AD rate. CONCLUSIONS: Quality assurance in obstetrics must balance the needs of two patients based on limited data. Our data shows the shortcomings of the prevailing performance indicator, CD rate, which does not correlate with birth outcomes for the pregnant patient or infant. The VUD rate provides an alternative that assesses both mode of delivery and labour outcomes. Shifting the quality lens to focus on VUD rate will provide a better metric that measures optimal outcomes for pregnant people and their babies. OBJECTIF: Cette étude vise à comparer le taux d'accouchement vaginal sans complications (AVSC), défini comme la proportion d'accouchements vaginaux (y compris par forceps ou ventouse) sans issue maternelle ou néonatale défavorable, au taux de césariennes en tant qu'indicateur de performance. MéTHODE: Il s'agit d'une analyse de cohorte rétrospective de données extraites d'une base de données provinciale sur tous les accouchements à terme pratiqués par un obstétricien dans une année, à l'exclusion des diagnostics empêchant le travail actif. La plupart des obstétriciens de cette province ont une pratique de consultation en obstétrique, principalement pour la prestation de soins de maternité primaires. Nous avons étudié la corrélation du taux d'événements indésirables (EI) à l'accouchement, mesuré par l'indice des issues défavorables (AOI), avec le taux de césariennes et le taux d'AVSC. RéSULTATS: Nous avons recensé 16 620 accouchements réalisés par 210 obstétriciens, pour un taux d'accouchement vaginal de 39,6 %; de ces accouchements vaginaux, 36,6 % étaient des accouchements assistés. Le taux global d'EI était de 9,9 %; le taux global d'AVSC, de 34 %. Alors que la césarienne et l'AVSC sont tous deux corrélés avec le mode d'accouchement, seul le taux d'AVSC est corrélé avec le taux d'EI. CONCLUSIONS: L'assurance de la qualité en obstétrique doit trouver un équilibre entre les besoins de deux patientes sur la base de données limitées. Nos données montrent les lacunes du taux de césariennes comme indicateur de performance dominant, car ce taux n'est pas corrélé avec les issues maternelles ou néonatales. Le taux d'AVSC serait une meilleure option, car il évalue à la fois le mode d'accouchement et les issues de l'accouchement. En considérant la qualité des soins à travers le prisme du taux d'AVSC, on obtiendrait un meilleur indicateur des issues optimales pour les personnes enceintes et leurs bébés.

Coefficients of variation analyses of internal quality control status for blood lead in China from 2015 to 2023.

BACKGROUND: Blood lead test is widely conducted in Chinese laboratories, while the imprecision of blood lead measurement based on internal quality control (IQC) across China has not been comprehensively evaluated nowadays. METHODS: Using the IQC data of blood lead collected through a web-based external quality assessment (EQA) reporting system, we analyzed current coefficients of variation (CVs) of blood lead from 2015 to 2023 among Chinese laboratories. Two allowable total error (TEa) imprecision levels from EQA were applied to calculate the pass rates, namely percentages of laboratories meeting precision quality specifications. Besides, CV values and pass rates by different subgroups were further performed to assess potential differences. RESULTS: Generally, median CV values significantly declined year by year from 6.8% in February 2015 to 5.9% in March 2023. The pass rates based on 1/3 TEa showed upward trends increasing from 15.3% in February 2015 to 20.0% in March 2023, but these percentages were non-ideal with less than 25%. No significant differences in CVs were found between tertiary hospitals and non-tertiary hospitals and between accredited and non-accredited laboratories. Significant time trends were observed in tertiary hospitals and nonaccredited laboratories. As for manufacturers, Bohui and self-made QC sample were most widely-used with obvious interannual declining trends of CVs. CONCLUSIONS: The CVs of blood lead demonstrated continuous overall improvements in the past twenty years. However, relatively lower pass rates indicated the non-ideal imprecision performance, and more proper performance specifications are warranted. Thus, imprecision improvement and ongoing investigation for blood lead IQC are still needed.