Establishment and evaluation of an autoverification scheme for hematology analysis in cancer patients / 中华检验医学杂志

Objective:According to the characteristics and common problems of hematology analysis in cancer patients, an autoverification scheme for cancer patients was formed, and the effectiveness and efficiency of the autoverification scheme were verified.Methods:The hematology review of international consensus and ourselves were respectively combined with Chinese multicenter autoverification rules to form two autoverification schemes. 10 063 blood samples (460 cases reviewed by microscope) were selected as the establishment group. Retrospective judgment was made in the instrument middleware, and various indexes such as autoverification pass rate and missed detection rate of different schemes were compared. By analyzing the data of missed cases one by one, the autoverification rules are adjusted according to the characteristics of diagnosis and treatment of cancer patients. By analyzing the platelet count variation range within 7 days in 19 300 cases, the Delta rules of platelet count were established. The platelet count Delta rules and the adjusted autoverification rules were combined to form the autoverification rules of our hospital and then combined with our hematology review rules to form the autoverification scheme of our hospital. The establishment group and verification group (10 876 cases, including 1 740 cases of microscopic examination) of the autoverification schemes were judged. The recognition function of Ethylenediaminetetraacetic acid-dependent pseudo thrombocytopenia (EDTA-PTCP) and PLT Delta check were programmed in the laboratory information system (LIS), and other rule judgment functions are performed in middleware. After four months of clinical trial application of 61 602 specimens, the effectiveness of our autoverification scheme was comprehensively evaluated.Results:The autoverification pass rates of international hematology review rules, our review rules, and Chinese multicenter autoverification rules are 46.36%, 52.26%, and the missed detection rates are 2.02%, 1.06%, respectively. The autoverification pass rates of our hospital autoverification scheme in the establishment group and the verification group are 51.19% and 52.78%, the missed detection rates are 0% and 0.03%, and the true positive rate are 100% and 99.95%, respectively. 56.06% of cases were passed automatically during the clinical trial application, and there were no missing cases, the true positive rate is 100%. The performance of our autoverification scheme is superior to the current autoverification schemes combined with mainstream hematology review rules and autoverification rules. The median time of TAT by autoverification was shortened by 15 minutes, and the 90th percentile time was shortened by 58 minutes, which was significantly lower than that of the same period last year. The marker function of "EDTA-PTCP" identified 31 special patients and 68 samples had been analyzed in total. After correction, the median increase of PLT was 76.5×10 9/L ( Z=-7.17, P<0.001). Conclusions:This study has established an autoverification scheme that combined by rules of hematology review and autoverification rules. It is suitable for cancer patients with high pass rate and very low rate of missed detection. This autoverification scheme can ensure the accuracy of the hematology analysis of cancer patients in our hospital and improve work efficiency.

Utilidad de los marcadores de remodelado óseo teniendo en cuenta el valor de referencia para el cambio / Clinical Utility of Bone Remodeling Markers Taking Into Account the Reference Value Change

La Modelación y el Remodelado de hueso son llevados a cabo a través del proceso de Recambio Óseo en sitios específicos llamados Unidades de Remodelación Ósea (URO). Este proceso puede evaluarse a través de marcadores bioquímicos de Formación y de Resorción que reflejan cambios globales del metabolismo esquelético. Estos marcadores de remodelado óseo son utilizados para investigación de enfermedades óseo-metabólicas, porque proveen información dinámica del metabolismo del hueso y pueden ser cuantificados en suero o en orina. La variación de estos marcadores se deben principalmente a variables preanalíticas, analíticas y biológicas y debe interpretarse teniendo en cuenta el Valor de Referencia para el Cambio significativo (VRC), que resulta de un cálculo en el que intervienen la variabilidad biológica (VB) del analito y el error aleatorio del método utilizado en el laboratorio.

The Modeling and Remodeling processes are conducted through the process of replacement bone at specific sites called Units Bone Remodeling (URO).These can be evaluated by biochemical markers of formation and resorption that reflect changes in skeletal metabolism. These markers of bone turnover are used for research óseo-metabolic diseases because they provide dynamic information of bone metabolism and can be quantified in serum or urine. The variation of these markers is mainly due to preanalytical, analytical and biological variables and should be interpreted taking into account the Reference Value Change (VRC), which results from a calculation in which the biological variability (VB) of the analyte and the random error of the method used in the laboratory are involved.

New Decision Criteria for Selecting Delta Check Methods Based on the Ratio of the Delta Difference to the Width of the Reference Range Can Be Generally Applicable for Each Clinical Chemistry Test Item

BACKGROUND: Many laboratories use 4 delta check methods: delta difference, delta percent change, rate difference, and rate percent change. However, guidelines regarding decision criteria for selecting delta check methods have not yet been provided. We present new decision criteria for selecting delta check methods for each clinical chemistry test item. METHODS: We collected 811,920 and 669,750 paired (present and previous) test results for 27 clinical chemistry test items from inpatients and outpatients, respectively. We devised new decision criteria for the selection of delta check methods based on the ratio of the delta difference to the width of the reference range (DD/RR). Delta check methods based on these criteria were compared with those based on the CV% of the absolute delta difference (ADD) as well as those reported in 2 previous studies. RESULTS: The delta check methods suggested by new decision criteria based on the DD/RR ratio corresponded well with those based on the CV% of the ADD except for only 2 items each in inpatients and outpatients. Delta check methods based on the DD/RR ratio also corresponded with those suggested in the 2 previous studies, except for 1 and 7 items in inpatients and outpatients, respectively. CONCLUSIONS: The DD/RR method appears to yield more feasible and intuitive selection criteria and can easily explain changes in the results by reflecting both the biological variation of the test item and the clinical characteristics of patients in each laboratory. We suggest this as a measure to determine delta check methods.

New Decision Criteria for Selecting Delta Check Methods Based on the Ratio of the Delta Difference to the Width of the Reference Range Can Be Generally Applicable for Each Clinical Chemistry Test Item

BACKGROUND: Many laboratories use 4 delta check methods: delta difference, delta percent change, rate difference, and rate percent change. However, guidelines regarding decision criteria for selecting delta check methods have not yet been provided. We present new decision criteria for selecting delta check methods for each clinical chemistry test item. METHODS: We collected 811,920 and 669,750 paired (present and previous) test results for 27 clinical chemistry test items from inpatients and outpatients, respectively. We devised new decision criteria for the selection of delta check methods based on the ratio of the delta difference to the width of the reference range (DD/RR). Delta check methods based on these criteria were compared with those based on the CV% of the absolute delta difference (ADD) as well as those reported in 2 previous studies. RESULTS: The delta check methods suggested by new decision criteria based on the DD/RR ratio corresponded well with those based on the CV% of the ADD except for only 2 items each in inpatients and outpatients. Delta check methods based on the DD/RR ratio also corresponded with those suggested in the 2 previous studies, except for 1 and 7 items in inpatients and outpatients, respectively. CONCLUSIONS: The DD/RR method appears to yield more feasible and intuitive selection criteria and can easily explain changes in the results by reflecting both the biological variation of the test item and the clinical characteristics of patients in each laboratory. We suggest this as a measure to determine delta check methods.

Quality control in Clinical Chemistry by "The Multi-Item Univariate Delta Check Method": The Multi-Item Univariate Delta Check Method / 대한의료정보학회지

Difficulties in calculation that hindered the practice of the delta check in the past is now no longer a problem thanks to the development of computers. But, high false positive rates, which creates heavy burden of checking-work load, are still a problem in the practice of the delta check. We propose a new approach to the reduction of false positive rates, naming our method "the multi-item univariate delta check (MIUDC) method". By the multi-item univariate delta check method, we mean a method in which univariate delta checks are performed on multiple items and specimens with the positive univariate delta check in at least k items receive a detailed investigation. Using data collected in the Department of Clinical Pathology at Korea University Guro Hospital via the Korea University Laboratory Information System, our research found that if we put specimens with positive univariate delta check in at least four test items (k=4) under a detailed investigation, check-out volumes will be light and efficiency will be high. As for test items deserving of more interest, total cholesterol, albumin, and total protein are appropriate because the false positive rate associated with them in the MIUDC was zero in a simulation study.

Differential application of rate and delta check on selected clinical chemistry tests

Through the present delta value check used in quality control programs is a powerful tool for detecting random errors in clinical chemistry analysis, it has some problems, such as missed true errors and delays in reporting time, because it also has the potential of showing erroneous positive results. Recently, new calculation methods for delta check with delta difference, delta percent change, rate difference, and rate percent change have been suggested by Lacher and Connelly (Clin Chem 34:1966-1970, 1988). Based on this new delta check method, we made the new criteria of which calculation method is applied to the clinical chemistry tests, i.e., the differential application of rate and delta check, and selectively applied the new method to 17 chemistry tests in order to solve the above problems. The applied criteria were the time dependence of the test item and the coefficient of variation of the absolute delta difference. Calcium, inorganic phosphorus, total protein, albumin, sodium, potassium, and chloride were classified as delta difference calculation method group; glucose and cholesterol as delta percent change group; creatinine, total and direct bilirubin as rate difference group; and urea nitrogen, uric acid, ALP, ALT, and AST as rate percent change group. With the previous criteria by Whitehurst et al. (Clin Chem 221:87-92) for 5045 specimens, the check-out rate was 47.8% (2,411 out of 5,045), and the positive predictive value was 0.41% (10 out of 2,411). For the new criteria, the check-out rate was 12.7% (621 out of 5,045), and the positive predictive value was 1.8% (nine out of 621).(ABSTRACT TRUNCATED AT 250 WORDS)