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The verification of examination procedures is a responsibility for clinical laboratories in order to guarantee that their performance characteristics comply with the specifications obtained during the validation process and are congruent with the intended scope of the assay. The aim was to perform an evaluation of precision, bias, linearity, linear drift, sample carry-over, and comparability of 73 assays from Siemens Healthineers, by following the CLSI EP10-A3 guidelines. The verification was performed by measuring 72 biochemical parameters in quality control (QC) materials from Bio-Rad (except for IL6) with 73 assays installed on eight measuring systems (five Atellica® CH 930 and three IM 1600 analyzers from Siemens Healthcare Diagnostics). The following information was collected: validation data from manufacturer, biological variation data from the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) database, and specifications for fßhCG and PAPP-A assays to meet the Fetal Medicine Foundation standards. A total of 17550 results were obtained during EP10 verification process. Out of the 73 methods, only Cl-S, Mg-S, and Na-S failed the criteria for adequate precision, trueness, and comparability. The assays did not show significant loss of linearity, linear drift, or sample carry-over. This study allowed the initial training and familiarization with the instruments and the identification of operational issues. It also represented an opportunity to evaluate the QCs and to obtain analytical performance information for application of sigma six metrics for quality assurance. Professionals are advised to adequately standardize and protocolize their verification processes to ensure laboratory competence and patient safety.

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The lack of standardization in the laboratory assessment of semen questions the reliability of semen analysis, and makes meaningful interpretation of these evaluations impossible. We herein describe a standardization program for morphology assessment currently in place in Australia and outline the methods used, both for the categorization of the abnormalities, including newly described abnormalities, and those that permit standardized microscopic assessment between laboratories.

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BACKGROUND: Testosterone (T) measurement in women is problematic leading to initiatives aiming to improve laboratory standardization of commercial assays. We assessed the impact on the clinical diagnosis of functional hyperandrogenic disorders of a total T immunoassay recently certified by the Centers for Diseases Control and Prevention (CDC). METHODS: We conducted a cross-sectional study including 263 consecutive adult premenopausal women presenting with functional ovarian hyperandrogenism-including polycystic ovary syndrome (PCOS)-and 73 nonhyperandrogenic female volunteers who served to define reference ranges. Total T was measured by a local routine direct radioimmunoassay and by a CDC-certified immunochemiluminescence assay. The main outcome measures were total and calculated free T concentrations and percentage of patients with hyperandrogenaemia. RESULTS: Both assays showed a poor concordance for total and calculated free T measurements. Hence, 147 (56%) and 109 (41%) of women had hyperandrogenaemia with the routine and CDC-certified assays, respectively [κ (95%CI): 0.538 (0.441-0.634)]. Free T levels calculated from total T using both assays showed similar correlations with metabolic variables. Women showing hyperandrogenaemia by both methods had the worst metabolic profiles, yet women presenting with hyperandrogenaemia only when using the CDC-certified assay did not show any significant difference compared to nonhyperandrogenic women in anthropometric or metabolic variables. Those women with hyperandrogenaemia only when using the routine assay were more obese and insulin resistant than normoandrogenaemic hirsute patients. CONCLUSIONS: An isolated androgen measurement, even a very specific one, is unlikely to identify the hyperandrogenic milieu that characterizes patients with functional ovarian hyperandrogenism and PCOS.

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BACKGROUND: In this study, we tested to which extent possible between-center differences in standardized operating procedures (SOPs) for biobanking of cerebrospinal fluid (CSF) samples influence the homogeneity of the resulting aliquots and, consequently, the concentrations of the centrally analyzed selected Alzheimer's disease biomarkers. METHODS: Proficiency processing samples (PPSs), prepared by pooling of four individual CSF samples, were sent to 10 participating centers, which were asked to perform aliquoting of the PPSs into two secondary aliquots (SAs) under their local SOPs. The resulting SAs were shipped to the central laboratory, where the concentrations of amyloid beta (Aß) 1-42, pTau181, and albumin were measured in one run with validated routine analytical methods. Total variability of the concentrations, and its within-center and between-center components, were analyzed with hierarchical regression models. RESULTS: We observed neglectable variability in the concentrations of pTau181 and albumin across the centers and the aliquots. In contrast, the variability of the Aß1-42 concentrations was much larger (overall coefficient of variation 31%), with 28% of the between-laboratory component and 10% of the within-laboratory (i.e., between-aliquot) component. We identified duration of the preparation of the aliquots and the centrifugation force as two potential confounders influencing within-center variability and biomarker concentrations, respectively. CONCLUSIONS: Proficiency processing schemes provide objective evidence for the most critical preanalytical variables. Standardization of these variables may significantly enhance the quality of the collected biospecimens. Studies utilizing retrospective samples collected under different local SOPs need to consider such differences in the statistical evaluations of the data.

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Posture changes have been known for a long time to influence the concentration of many analytes in blood especially macromolecules. It is very clear that when someone switches from supine to sitting or standing or from sitting to standing a hemoconcentration is induced. Similarly, when someone switches from standing to sitting or lying a hemodilution occurs. In the context of clinical chemistry, rules have been issued to buffer the impact of postural changes close to the blood specimen collection (e.g. 15 min of seated rest before the blood puncture). A big work has then been performed to educate the personnel concerned by blood specimen collection (medical doctors, nurses, phlebotomists, pharmacists, clinical researchers, scientists, etc.) through professional training to standardize the puncture and the collection procedures. Official procedures and guidelines have been published. Nevertheless, there is still a long way to go and too often standardization of posture before the blood collection is not properly performed. Maybe, this relative failure could be overcome by using new strategies in forwarding the message on the impact of posture changes in the outcome of blood tests and the importance of controlling this factor when blood specimens are taken. Some possible actions are presented concerning the improvement of the education of medical and paramedical personnel especially during their primary training, and also to educate the patients and the whole population in general.

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Fractional exhaled nitric oxide (FENO) assesses eosinophilic inflammation of the airways, but FENO values are also influenced by oral nitric oxide (NO). The aim of this pilot study was to measure FENO and compare the effect of two different mouthwashes on FENO and analyse the duration of the effect. FENO was measured in 12 randomized volunteers (healthy or asthmatic subjects) with a NIOX VERO® analyser at an expiratory flow rate of 50 mL/s. After a baseline measurement, a mouthwash was performed either with tap water or carbonated water and was measured during 20 min in 2 min intervals. The procedure was repeated with the other mouthwash. We found that both mouthwashes reduced FENO immediately at the beginning compared to the baseline (p < .001). The carbonated water mouthwash effect lasted 12 min (p ranging from <0.001 to <0.05). The tap water mouthwash reduced FENO statistically significantly only for 2 min compared with the baseline. We conclude that a single carbonated water mouthwash can significantly reduce the oropharyngeal NO contribution during a 12 min time interval.

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Sigma metrics can be used to predict assay quality, allowing easy comparison of instrument quality and predicting which tests will require minimal quality control (QC) rules to monitor the performance of the method. A Six Sigma QC program can result in fewer controls and fewer QC failures for methods with a sigma metric of 5 or better. The higher the number of methods with a sigma metric of 5 or better, the lower the costs for reagents, supplies, and control material required to monitor the performance of the methods.

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The French-Speaking Cellular Haematology Group (GFHC) recently published criteria for microscopic analysis of a blood smears when a hemogram is requested. In order to evaluate and improve these recommendations using an XN (Sysmex) analyzer, we assessed 31,836 samples categorized into two sub-groups of patients either receiving or not receiving care in the clinical hematology/oncology departments of two university hospitals. By combining the manufacturer's recommendations and the GFHC recommendations, 21.3% of samples had a positive review flag in phase 1 of our study (17,991 samples). In phase 2 (13,845 samples), increasing the immature granulocytes (IG) percentage from 5-10% as a review trigger threshold, and ignoring slides with isolated flags 'PLT HIGH' (thrombocytosis) or 'MCV LOW' (microcytosis) or 'Blast/Abn Lymph and Atypical Lymph' (blast cells/abnormal lymphocytes and atypical lymphocytes) (in the absence of abnormal cells on a previous blood smear within 72 h), enabled us to significantly reduce the number of slides reviewed from 21.3-15.0% (p < 0.0001), without loss of clinical value. This decrease occurred in both sub-groups (hematology 48.7-38.0%, non-hematology 18.3-11.7%, p < 0.0001). In conclusion, the application of the GFHC criteria adapted to XN analyzers has enabled us to optimize the hematology laboratory processes, and thus reduce the production costs and the turnaround time of hemogram results.

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INTRODUCTION: The results of urine sediment analysis have been reported semiquantitatively. However, as recent guidelines recommend quantitative reporting of urine sediment, and with the development of automated urine sediment analyzers, there is an increasing need for quantitative analysis of urine sediment. Here, we developed a protocol for urine sediment analysis and quantified the results. METHODS: Based on questionnaires, various reports, guidelines, and experimental results, we developed a protocol for urine sediment analysis. The results of this new protocol were compared with those obtained with a standardized chamber and an automated sediment analyzer. Reference intervals were also estimated using new protocol. RESULTS: We developed a protocol with centrifugation at 400 g for 5 min, with the average concentration factor of 30. The correlation between quantitative results of urine sediment analysis, the standardized chamber, and the automated sediment analyzer were generally good. The conversion factor derived from the new protocol showed a better fit with the results of manual count than the default conversion factor in the automated sediment analyzer. CONCLUSIONS: We developed a protocol for manual urine sediment analysis to quantitatively report the results. This protocol may provide a mean for standardization of urine sediment analysis.

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OBJECTIVE: Microparticles (MP) are actively involved in the hypercoagulable state reported both in normal pregnancies and in pregnancy diagnosed with placenta-mediated complications. In this study the origin and the levels of plasma MP as well as MP activity were evaluated in a group of healthy women during the three trimesters of a normal pregnancy. MATERIALS AND METHODS: Seventy-five healthy normotensive pregnant women were enrolled and blood samples were prospectively collected at three different time points corresponding to 1st trimester, 2nd trimester, 3rd trimester of pregnancy. A group of age- matched healthy non-pregnant women acted as controls. Both standard clotting parameters and MP of different origin were measured. MP were identified by size and annexin V- FITC labelling using flow-cytometer. MP subtypes were identified using specific monoclonal antibodies. Procoagulant activity of MP was assessed using the STA® Procoag PPL assay. RESULTS: The levels of total, platelet-, endothelial-, leukocyte-derived and tissue factor-bearing MP, as well as the MP procoagulant activity, in non-complicated pregnancy were higher in the 1st trimester as compared to non-pregnant age-matched women. Regardless of the origin, MP levels gradually increase during pregnancy, with the highest values reached in the 3rd trimester. CONCLUSIONS: MP levels gradually increase during normotensive pregnancy. All types of MP including TF+ present with the highest levels in the 3rd trimester. MP convey prothrombotic and proinflammatory antigens already from the first trimester of normal pregnancy. This may contribute to the global hypercoagulable state observed, particularly in the last months of pregnancy, also in healthy women.

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BACKGROUND: Documentation is very important; a considerable number of documents exist for use in accreditation inspection. However, most laboratories do not effectively manage the processes of documentation, organization, and storage. The purpose of this study was to facilitate the establishment of a strategically effective and sustainably standardized document management system. METHODS: A document code formatting system was modified by comparing the document list data received from 3 major university hospitals. In addition, a questionnaire regarding document code standardization was created and sent to 268 institutes to establish document classifications and generate a standard coding scheme. A computerized document management system was developed. RESULTS: Only 32% (8 out of 25 institutes) answered that they were able to identify all of the document types and their numbers. In total, 76% of institutes (19 out of 25) answered that a systematic document management system was necessary. Disorganized document files were systemized by classifying them into 8 major groups according to their characteristics: patient test records (T), test quality control (Q), manuals (M), equipment and environment management (E), statistics (S), division administration (A), department administration (R), and others (X). CONCLUSIONS: Our documentation system may serve as a basis for the standardization of documents and the creation of a document management system for all hospital laboratories.

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BACKGROUND: Documentation is very important; a considerable number of documents exist for use in accreditation inspection. However, most laboratories do not effectively manage the processes of documentation, organization, and storage. The purpose of this study was to facilitate the establishment of a strategically effective and sustainably standardized document management system. METHODS: A document code formatting system was modified by comparing the document list data received from 3 major university hospitals. In addition, a questionnaire regarding document code standardization was created and sent to 268 institutes to establish document classifications and generate a standard coding scheme. A computerized document management system was developed. RESULTS: Only 32% (8 out of 25 institutes) answered that they were able to identify all of the document types and their numbers. In total, 76% of institutes (19 out of 25) answered that a systematic document management system was necessary. Disorganized document files were systemized by classifying them into 8 major groups according to their characteristics: patient test records (T), test quality control (Q), manuals (M), equipment and environment management (E), statistics (S), division administration (A), department administration (R), and others (X). CONCLUSIONS: Our documentation system may serve as a basis for the standardization of documents and the creation of a document management system for all hospital laboratories.

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