Biochemia medica最新文献

{"title":"Use of Hoteling's T² multivariate control chart for effective monitoring of a laboratory test with a 3-level quality control scheme.","authors":"Cristiano Ialongo","doi":"10.11613/BM.2025.020701","DOIUrl":"10.11613/BM.2025.020701","url":null,"abstract":"<p><strong>Introduction: </strong>A control chart based on Hotelling's T² multivariate statistics was used to monitor the quality of an immunoenzymatic assay for plasma levetiracetam. The chart incorporated a multi-level quality control (MLQC) system with three concentration levels of the analyte and included the analytical performance specification (APS) for therapeutic drug monitoring.</p><p><strong>Materials and methods: </strong>Data were collected from March 1 to August 14, 2024, comprising 84 consecutive triplets of values for the three MLQC levels. The initial 59 triplets were used to estimate the variance-covariance matrix and vector of means (phase I). These estimates were then applied to calculate Hotelling's T² for the remaining 25 triplets (phase II). The pharmacokinetic model of Fraser was employed to derive the APS for levetiracetam, based on a twice-daily dosing scheme and a median half-life of 8 hours.</p><p><strong>Results: </strong>The three MLQC levels showed significant correlations (r > 0.6) in both control phases. The Hotelling's T² control chart detected no out-of-specifications states (OC), compared to 12 OC signals from individual Levey-Jennings charts monitoring the MLQC levels separately. The integration of the APS into the Hotelling's T² chart provided additional insights into the process quality, and in two instances, it aligned with the OC signal from at least one of the Levey-Jennings charts.</p><p><strong>Conclusions: </strong>Hotelling's T² multivariate chart is effective for internal quality control of laboratory tests. As MLQC data offer correlated information, this approach is advantageous over multiple individual univariate charts as it ensures the correct level of false positive and false negative alarms.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 2","pages":"020701"},"PeriodicalIF":0.0,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12131413/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144228236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Post-exercise creatine kinase variability: a literature review.","authors":"Vanja Radišić Biljak, Anja Lazić, Ana Nikler, Damir Pekas, Andrea Saračević, Nebojša Trajković","doi":"10.11613/BM.2025.020502","DOIUrl":"10.11613/BM.2025.020502","url":null,"abstract":"<p><p>Creatine kinase (CK) activity has been generally considered as reliable blood marker for assessing muscle function, damage, and repair. However, the greatest challenge in the interpretation of CK activity remains the high variability in CK increase in relation to degrees of muscle cell damage or disturbance. Several known contributors to CK variability have been identified. The most important include the type of training, exercise intensity, gender differences, body composition, intra- and interindividual biological variability, as well as preanalytical and analytical considerations. Creatine kinase variability following different types of exercise reflects the complex interplay between exercise modality, intensity, individual physiology, and recovery strategies. High-intensity exercises, especially those involving eccentric muscle contractions, tend to produce more significant CK responses due to greater muscle fiber disruption. Gender differences in CK variability are pronounced, with men generally exhibiting higher CK activities following exercise compared to women. Creatine kinase variability is also closely linked to body composition, with muscle mass generally leading to higher CK activities post-exercise, while higher body fat may correlate with lower CK responses. Regarding preanalytical and analytical considerations, perhaps the greatest challenge in CK measurement is the limited sample stability, which should always be taken into consideration when analyzing CK activity in stored samples for research or clinical purposes. This review, through exploring all of the above-mentioned sources of CK variability, could facilitate the development of evidence-based practices for preventing overuse injuries, and promoting long-term athlete health and well-being.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 2","pages":"020502"},"PeriodicalIF":0.0,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12161516/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144304269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of demand management on vitamin D testing.","authors":"Juan José Perales-Afán, Diego Aparicio-Pelaz, Juan José Puente-Lanzarote, Marta Fabre","doi":"10.11613/BM.2025.020707","DOIUrl":"10.11613/BM.2025.020707","url":null,"abstract":"<p><strong>Introduction: </strong>25-hydroxyvitamin D (25-OH-D) is essential for calcium homeostasis and bone health, with increasing evidence suggesting associations with non-skeletal diseases. However, the lack of consensus on optimal concentrations and laboratory variability has led to clinical uncertainty and excessive testing. This study evaluates the impact of demand management strategies and revised cut-off points on test volumes, unperformed determinations, and cost savings.</p><p><strong>Material and methods: </strong>A retrospective study (January 2015-May 2024) analyzed all 25-OH-D requests. Concentrations of 25-OH-D were measured using electrochemiluminescence assays on a Cobas C8000. An annual trend analysis of 25-OH-D test requests was performed to evaluate changes in demand. In 2018, vitamin D deficiency prevalence was assessed according to three cut-off values (75, 50 and 30 nmol/L). We assessed the impact of demand management rules, implemented in May 2022, to reduce unnecessary testing. The follow-up testing rate was calculated as the proportion of repeat tests within 12 months after determination.</p><p><strong>Results: </strong>There was 25-OH-D testing increased from 10,830 in 2015 to nearly 85,000 in 2023. Demand management strategies led to 12,406 rejections in 2022 (from May onwards), 16,809 in 2023, and 7566 in 2024 (until May), saving €85,600. Follow-up testing rates dropped from ~15% before 2022 to ~5% afterward. Lowering the deficiency threshold from 75 to 50 nmol/L reduced deficiency diagnoses from > 70% to < 50%; at 30 nmol/L, rates could drop to ~10-11%.</p><p><strong>Conclusions: </strong>Demand management strategies effectively reduce unnecessary testing and healthcare costs. Establishing appropriate reference values prevents overestimation of vitamin D deficiency, optimizing clinical and economic outcomes.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 2","pages":"020707"},"PeriodicalIF":0.0,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12161517/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144304272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Routine data analysis for moderate hemolysis interference correction in neuron specific enolase quantification.","authors":"Leyre Ruiz, Tomás Munoz, Alvaro González, Estibaliz Alegre","doi":"10.11613/BM.2025.020802","DOIUrl":"10.11613/BM.2025.020802","url":null,"abstract":"<p><strong>Introduction: </strong>Serum neuron specific enolase (NSE) is used as neuroendocrine tumor and central nervous system damage marker. It is present in variable concentrations in erythrocytes and hemolysis interferes in serum NSE quantification. Our aim was to develop a correction formula for moderate hemolysis, based on repeated patient samples instead of artificial sample doping with hemolysates.</p><p><strong>Materials and methods: </strong>We searched in laboratory informatics system for patients with sample pairs obtained within 24 h, for NSE quantification. We registered NSE and hemolytic index (NSE1 and HI1) from the first moderate hemolyzed sample (HI: 15-80), and from the second non-hemolyzed sample obtained afterwards (NSE2 and HI2). In a development cohort (N = 41), we obtained the formula NSE_calc = NSE1 - (0.354 x (HI1 - HI2)) - 0.162, which was later used in the validation cohort (N = 26) to calculate NSE corrected concentrations (NSE_calc).</p><p><strong>Results: </strong>Concentrations of NSE2 differed from NSE1 (P = < 0.001) but not from NSE_calc (P = 0.291). In 84% samples, NSE1 had a relative bias from NSE that exceeded the 14% limit of total error allowable, with a median relative bias of 22.5%. Meanwhile, the bias between NSE2 concentrations and NSE_calc was - 0.4 µg/L (95% confidence interval = - 3.8 to 4.5), the relative bias was 8.3% and only 23% of samples exceeded the 14% limit. Formula usefulness was limited to moderate hemolytic samples.</p><p><strong>Conclusions: </strong>In summary, with this innovative approach, the NSE_calc bias is low enough to have clinical significance, so re-drawings of blood samples might be avoided. This approach also opens the possibility to correct the estimation of other magnitude concentrations affected by <i>in vitro</i> hemolysis.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 2","pages":"020802"},"PeriodicalIF":0.0,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12161513/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144304271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strategic use of Big Data: implementing reference intervals for serum folate and serum cobalamin.","authors":"Alicia Madurga, Ariadna Arbiol-Roca, Maria Rosa Navarro-Badal, Anna Cortes-Bosch de Basea, Dolors Dot-Bach","doi":"10.11613/BM.2025.010705","DOIUrl":"10.11613/BM.2025.010705","url":null,"abstract":"<p><strong>Introduction: </strong>Defining trustworthy reference intervals (RIs) for serum folate (FOL) or serum cobalamin (VITB12) is a difficult task. The purpose of this study is to use an indirect approach from the laboratory information's system to indirectly generate RIs for FOL and VITB12.</p><p><strong>Materials and methods: </strong>A retrospective observational study was performed at a tertiary-care laboratory's hospital during 12 months. All FOL and VITB12 tests were measured using a Cobas8000 e801 system (Roche Diagnostics, Mannheim, Germany). The RIs were calculated using a non-parametric approach. The RIs established in the present study were verified by calculating the fraction of RIs that fell outside the new RIs, in two validation cohorts sampled using the direct and indirect method.</p><p><strong>Results: </strong>A total of 19,214 (FOL) and 27,420 (VITB12) results were obtained. The RIs were 4.5 nmol/L (90% confidence intervals (CI) 4.4-4.6) to 38.4 nmol/L (CI 38.3-38.5) for FOL and 140 pmol/L (CI 139-141) to 659 pmol/L (CI 657-660) for VITB12. The verification included 8,798 FOL results and 7,365 VITB12 results. For both magnitudes was acceptable since only 0.1% of FOL and 0.02% of VITB12 results fell outside the RIs. Finally, the RIs were verified using a direct method with twenty individuals. For FOL 20/20 cases and 19/20 of VITB12 cases fell within the estimated RIs.</p><p><strong>Conclusions: </strong>In summary, the use of an indirect data approach has enabled us to calculate RIs for FOL and VITB12. The RIs obtained in our study are lower than those proposed by the manufacturer for both FOL and VITB12.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 1","pages":"010705"},"PeriodicalIF":0.0,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11838714/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143461557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding green discoloration in serum and citrate plasma samples: a case report.","authors":"Iva Friščić, Sonja Perkov, Mirjana Mariana Kardum Paro","doi":"10.11613/BM.2025.011001","DOIUrl":"10.11613/BM.2025.011001","url":null,"abstract":"<p><p>This case report investigates the occurrence of green discoloration in serum and citrate plasma samples collected from a male adult patient following a multivisceral organ transplant. In collected samples, it was necessary to investigate the influence of sample discoloration on the results of laboratory tests and to determine the appropriate approach to sample management. Hematology, coagulation and blood gas analysis showed no flags, but the biochemical lipemia index was susceptible to positive interference, necessitating dilution of the native sample. Despite the green discoloration, both native and diluted samples exhibited minimal interference on routine clinical chemistry analyses, demonstrating the reliability of the laboratory test results. This case report underscores the influence of preanalytical factors on the results of laboratory tests, the need for a thorough assessment of the sample adequacy for laboratory testing and the strict application of appropriate guidelines in the sample management in order to make an accurate diagnosis and ensure optimal patient care.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 1","pages":"011001"},"PeriodicalIF":0.0,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11654241/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142866906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"National recommendations of the Working Group for Post-analytics of the Croatian Society of Medical Biochemistry and Laboratory Medicine: implementation of autovalidation procedures.","authors":"Vladimira Rimac, Jelena Vlašić Tanasković, Anja Jokić, Lorena Honović, Sonja Podolar, Jasna Leniček Krleža","doi":"10.11613/BM.2025.010503","DOIUrl":"10.11613/BM.2025.010503","url":null,"abstract":"<p><p>Autovalidation is a computerised postanalytical tool that uses a sequence of procedures to verify laboratory test results without manual intervention. The Working Group for Post-analytics of the Croatian Society for Medical Biochemistry and Laboratory Medicine has prepared procedures for the implementation of autovalidation in routine laboratory work, which complement the existing national recommendations and aim to clarify the procedures of autovalidation. Before implementation, it is necessary to determine the need for the introduction of autovalidation in routine laboratory work, and then appoint the autovalidation team, whose task is to decide in which area of laboratory work autovalidation should be introduced, create the algorithm and supervise the verification of autovalidation. Standard rules included in the algorithm are patient data, messages from the analyzer, values of interference indices, autovalidation range and delta check. All criteria defined in the autovalidation algorithm have to be documented and approved by the laboratory manager. This autovalidation procedure shows the basic rules of autovalidation that can be used by any laboratory in the initial phase. The justification for using autovalidation will depend on the number and complexity of laboratory tests, the size of the laboratory personnel, and the available financial and material resources. Autovalidation avoids the subjective evaluation of laboratory test results as it is based on the same rules and is standardised to a certain extent, which further increases the quality of laboratory test results.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 1","pages":"010503"},"PeriodicalIF":0.0,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11838716/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143461555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Levothyroxine therapy reduces endocan and total cholesterol concentrations in patients with subclinical hypothyroidism.","authors":"Tihana Serdar Hiršl, Koraljka Đurić, Marina Čeprnja, Ivana Zec, Marijana Kraljević Šmalcelj, Tomislav Jukić, Tanja Bobetić-Vranić, Anita Somborac-Bačura","doi":"10.11613/BM.2025.010703","DOIUrl":"10.11613/BM.2025.010703","url":null,"abstract":"<p><strong>Introduction: </strong>Subclinical hypothyroidism (SCH) is an independent risk factor for cardiovascular diseases due to endothelial dysfunction and atherosclerosis development. The aim of this study was to determine whether the levothyroxine therapy could impact the concentrations of endothelial dysfunction blood markers, namely endothelin-1 (ET-1), asymmetric dimethylarginine (ADMA) and endocan, in patients with a mild form of SCH (thyroid-stimulating hormone (TSH) ≤ 10 mIU/L).</p><p><strong>Materials and methods: </strong>In this case-control prospective study, SCH patients and healthy controls were recruited during their regular health examinations. Medical specialists prescribed levothyroxine to SCH patients if necessary. The endothelial dysfunction markers, as well as other biochemical markers, were measured in all subjects at baseline, and after 6 months of levothyroxine treatment following the euthyroidism.</p><p><strong>Results: </strong>Our study showed higher ADMA (248.00 (168.78-540.20) <i>vs</i>. 166.30 (140.60-243.40) μg/L, P = 0.002), endocan (114.30 (63.45-194.65) <i>vs</i>. 67.26 (50.80-126.10) ng/L, P = 0.004), low-density lipoprotein cholesterol (LDL) (3.3 ± 0.6 <i>vs</i>. 3.7 ± 0.9 mmol/L, P = 0.043) and non-high-density lipoprotein cholesterol (non-HDL) (3.8 ± 0.7 <i>vs</i>. 4.2 ± 1.0 mmol/L, P = 0.020) concentrations in patients with a mild form of SCH in comparison with healthy subjects. In SCH patients, after 6 months of levothyroxine treatment following the euthyroidism, we observed a significant decrease in endocan (91.47 (61.88-200.03) <i>vs</i>. 97.90 (55.18-154.88) ng/L, P = 0.004), and total cholesterol concentrations (CHOL) (6.2 ± 1.0 <i>vs</i>. 5.8 ± 1.0 mmol/L, P = 0.039).</p><p><strong>Conclusions: </strong>A mild form of SCH is associated with higher concentrations of endocan, ADMA, LDL and non-HDL. The potential benefits of levothyroxine therapy were shown through the significant decrease of endocan and CHOL concentrations in SCH patients, thus contributing the atherosclerosis prevention.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11654239/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142866864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proposal for delta check limits of frequently requested hormones using real-world data.","authors":"Sunghwan Shin, Shinae Yu, Sollip Kim, Soo Jin Yoo, Eun-Jung Cho, Jae-Woo Chung","doi":"10.11613/BM.2025.010704","DOIUrl":"10.11613/BM.2025.010704","url":null,"abstract":"<p><strong>Introduction: </strong>Research on delta check limits (DCLs) for hormones is limited, yet some laboratories apply arbitrary DCLs. We aimed to propose DCLs for commonly requested hormones.</p><p><strong>Materials and methods: </strong>This study analyzed 59,657 paired results for adrenocorticotropic hormone (ACTH), cortisol, parathyroid hormone (PTH), prolactin, insulin, testosterone, and thyroglobulin from five Korean university hospitals. Delta check limits were established using the absolute delta difference (absDD) and absolute delta percent change (absDPC) with 5% cutoff for inpatients/emergencies (IE), outpatients (O) and both (combined; mean of them). Proportions outside the DCLs were compared across groups.</p><p><strong>Results: </strong>Using absDD and absDPC, each group's DCLs showed 4.3% to 6.4% of values outside the DCLs, aligning with the 5% cutoff (excluding group IE for insulin, testosterone, and thyroglobulin due to < 1000 data pairs). Delta check limits of absDD differed between groups for ACTH, cortisol, PTH, and prolactin, while for absDPC, differences were seen only for ACTH and prolactin. Cross-validation revealed IE and O groups differed outside DCLs of absDD for ACTH, cortisol, and PTH, but only ACTH with absDPC. Combined DCLs of absDD showed ACTH and cortisol exceeded limits in 7.2% and 9.0% in IE, but only 2.6% and 0.6% in O. With absDPC, ACTH differed (10.4% in IE, 2.8% in O), while cortisol, PTH, and prolactin ranged from 4.0% to 6.1%.</p><p><strong>Conclusions: </strong>Combined DCLs of absDPC are recommended for cortisol, PTH, and prolactin, while ACTH requires separate DCLs on clinical settings. These DCLs from real-world data provide a foundation for establishing DCLs of hormones in clinical laboratories.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 1","pages":"010704"},"PeriodicalIF":0.0,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11838720/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143461556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implementation of new Westgard rules suggested by the Westgard Advisor software for five immunological parameters.","authors":"Lisa Cristelli, Francesca Occhipinti, Daniel Tumiatti, De Luisi Antonia, Erika Jani, Massimo Daves","doi":"10.11613/BM.2025.010701","DOIUrl":"10.11613/BM.2025.010701","url":null,"abstract":"<p><strong>Introduction: </strong>Knowledge and systematic evaluation of analytical errors is the task of internal analytical quality control management. The aim of this study was to assess whether the Westgard rules proposed by Bio-Rad's Westgard Advisor software are more efficient in the monitoring of analytical performance than those previously in use.</p><p><strong>Materials and methods: </strong>The study was carried out on the nephelometer Atellica NEPH630 (Siemens Healthineers, Erlangen, Germany). Five parameters were chosen: serum immunoglobulin A (IgA), alpha 1 - antitrypsin (AAT), prealbumin, lipoprotein (a) (Lp(a)) and ceruloplasmin. The study was divided into 4 phases (A, B, C, D): phase A - old rules used (1_3s, R_4s and 2_2s); phase B - first introduction of new rules (30 days), (1_3s/2_2s for IgA; 1_3s/2_2s/R_4s/4_1s/10_x for the remaining parameters); Phase C - second intervention (after 60 days) 1_3s/2_2s/R_4s/4_1s for IgA and Lp(a), 1_3s/2_2s/R_4s/4_1s/8_x for prealbumin and ceruloplasmin and 1_3s/2_2s/R_4s/4_1s/10_x for AAT; and Phase D - values at the end of the study (1_3s for IgA, 1_3s/2_2s/3_2s/R_4s/3_1s/12_x for AAT and ceruloplasmin, 1_3s/2_2s/R_4s/4_1s/8_x for prealbumin and 1_3s/2_2s/R_4s/4_1s/10_x for Lp(a).</p><p><strong>Results: </strong>At the end of the study the coefficient of variation (CV%), bias (%) and sigma for IgA were 2.55%, - 1.09% and 5.33, respectively; for AAT 3.88, - 2.21 and 3.25; for prealbumin 3.99, - 0.14 and 2.95; for Lp(a) 8.02, - 0.34 and 3.81; for ceruloplasmin 2.48, - 3.65 and 3.49.</p><p><strong>Conclusions: </strong>By using newly suggested rejection rules, we did not observe an improvement in monitoring of analytical performance.</p>","PeriodicalId":94370,"journal":{"name":"Biochemia medica","volume":"35 1","pages":"010701"},"PeriodicalIF":0.0,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11654237/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142866772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}