Abstract:
:Autocorrelation of clinical chemistry quality-control (Q/C) measurements causes one of the basic assumptions underlying the use of Levey-Jennings control charts to be violated and performance to be degraded. This is the requirement that the observations be statistically independent. We present a proposal for a new approach to statistical quality control that removes this difficulty. We propose to replace the current single control chart of raw Q/C data with two charts: (a) a common cause chart, representing a Box-Jenkins ARIMA time-series model of any underlying persisting nonrandomness in the process, and (b) a special cause chart of the residuals from the above model, which, being free of such persisting nonrandomness, fulfills the criteria for use of the standard Levey-Jennings plotting format and standard control rules. We provide a comparison of the performance of our proposed approach with that of current practice.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Alwan LC,Bissell MGsubject
Has Abstractpub_date
1988-07-01 00:00:00pages
1396-406issue
7eissn
0009-9147issn
1530-8561journal_volume
34pub_type
杂志文章abstract::Measurement of the mass concentration of serum enzymes by radioimmunoassay provides direct quantitation of specific isoenzymes and may be less subject to some of the limitations of traditional assay procedures for enzymes. We describe the development of a sensitive and specific radioimmunoassay for the muscle isoenzym...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-03-01 00:00:00
abstract::Serum amyloid A (SAA), a sensitive acute-phase protein, is the precursor of AA fibrils in reactive amyloidosis. However, SAA is poorly immunogenic, and development and standardization of immunoassays of this protein have been difficult. We established an automated polyclonal/monoclonal microparticle capture enzyme imm...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-07-01 00:00:00
abstract:BACKGROUND:Although minimum regulatory standards exist for determining QC testing frequency, decisions regarding when and how to run QC samples are not standardized. Most QC testing strategies test control samples at fixed time intervals, often placing the samples in the same position on an instrument during subsequent...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.083311
更新日期:2007-04-01 00:00:00
abstract:BACKGROUND:It is important that cardiac troponin be measured accurately with a robust method to limit false results with potentially adverse clinical outcomes. In this study, we characterized the robustness of 4 analytical platforms by measuring the outlier rate between duplicate results. METHODS:We measured cardiac t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2010.159830
更新日期:2011-05-01 00:00:00
abstract:BACKGROUND:Epidemiologists have observed that blood donation is associated with decreased risk of type 2 diabetes and cardiovascular disease. METHODS:We investigated the relationship between iron stores and insulin sensitivity, after controlling for known confounding factors, and compared insulin sensitivity between b...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.046847
更新日期:2005-07-01 00:00:00
abstract::Two families with benign hyperphosphatasemia of intestinal origin were studied and compared with six other cases reported in the literature. No evidence of clinical abnormalities or explanations for the unusual enzyme concentrations were found. Agarose gel electrophoresis of alkaline phosphatase (ALP, EC 3.1.3.1) isoe...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1991-08-01 00:00:00
abstract::We describe a case of sulfhemoglobinemia associated with toxic paint ingestion. Blood gases, oxygen content, and fractional hemoglobin derivatives were assayed with Radiometer 520 and OSM3 instruments. Although the CO-oximeters indicated the presence of sulfhemoglobin (SulfHb), the results were not quantitative. An OS...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-01-01 00:00:00
abstract::The concentrations of 25 plasma proteins were measured in 22 patients with membranous nephropathy. For some large proteins, the plasma concentrations were increased; there were also large proteins with low plasma concentrations, but small or medium-sized proteins showed uniformly lower plasma concentration than the co...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-07-01 00:00:00
abstract:BACKGROUND:Plasma amino acid (PAA) profiles are used in routine clinical practice for the diagnosis and monitoring of inherited disorders of amino acid metabolism, organic acidemias, and urea cycle defects. Interpretation of PAA profiles is complex and requires substantial training and expertise to perform. Given previ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa134
更新日期:2020-09-01 00:00:00
abstract:BACKGROUND:Growth differentiation factor 15 (GDF15), a stress-responsive cytokine produced in cardiovascular cells under conditions of inflammation and oxidative stress, is emerging as an important prognostic marker in individuals with and without existing cardiovascular disease (CVD). We therefore examined the clinica...
journal_title:Clinical chemistry
pub_type: 杂志文章,meta分析
doi:10.1373/clinchem.2012.190322
更新日期:2012-11-01 00:00:00
abstract::The method is based on the selective activating capacity of dithiothreitol on creatine kinase isoenzyme MB, after isoenzyme MM is activated by glutathione. Isolated isoenzymes MM and MB of human and canine origin were assayed individually and in mixtures of known activities. When glutathione was present in the assay m...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-10-01 00:00:00
abstract:BACKGROUND:Platelet-derived microparticles (PMPs) are generally considered a marker of platelet activation in cardiovascular disease. We studied the extent to which PMP subpopulations parallel platelet activation in vitro and in vivo. METHODS:Using flow cytometry, we analyzed PMP subpopulations from resting and activa...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:10.1373/clinchem.2005.057414
更新日期:2006-04-01 00:00:00
abstract:BACKGROUND:Immune repertoire sequencing of the T-cell receptor can identify clonotypes that have expanded as a result of antigen recognition or hematological malignancies. However, current sequencing protocols display limitations with nonuniform amplification and polymerase-induced errors during sequencing. Here, we de...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa159
更新日期:2020-09-01 00:00:00
abstract:BACKGROUND:Recent recognition of its broad pathophysiological importance has triggered an increased interest in 25-hydroxyvitamin D [25(OH)D]. By consequence, throughput in 25(OH)D testing has become an issue for clinical laboratories, and several automated assays for measurement of 25(OH)D are now available. The aim o...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.176545
更新日期:2012-03-01 00:00:00
abstract::We review atomic flame spectrometry of metals based on the selective laser-enhancement of the rate of atomic ionization. A discussion of basic principles, prior literature, and instrumentation is followed by an overview of analytical figures of merit for the technique, and a look at its present status and areas for fu...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-09-01 00:00:00
abstract::Two hundred patients with liver disease were re-studied after six to eight years. The initial routine diagnosis (mainly based on morphological criteria) was confirmed in almost 80% of cases of chronic liver disease. In chronic active hepatitis, agreement was found in 86%. An alternative classification based on cluster...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-05-01 00:00:00
abstract:BACKGROUND:In malignancy, gene mutations frequently occur in tumor suppressor genes such as p53 and are sporadically located. We describe a homogeneous method for amplification and mutation scanning, and apply the method to the p53 gene. METHODS:Using a series of overlapping fluorescein-labeled oligonucleotides comple...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-08-01 00:00:00
abstract:BACKGROUND:Screening for heterozygous sequence changes in PCR products, also known as "mutation scanning", is an important tool for genetic research and clinical applications. Conventional methods require a separation step. METHODS:We evaluated the sensitivity and specificity of homogeneous scanning, using a saturatin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2003.029751
更新日期:2004-10-01 00:00:00
abstract::The immunoreactivity of anti-triiodothyronine (anti-T3) IgG, pretreated at acidic pH and adsorbed onto polystyrene beads, was significantly greater than that determined for native anti-T3 IgG immobilized at optimum pH 3.5. Acidic-pH-pretreated IgG, adsorbed at pH 7.0 onto ethanol-treated beads, had less immunoreactivi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-03-01 00:00:00
abstract::We have developed a fully enzymatic method to measure 1,5 anhydro-D-glucitol (1,5-AG) in serum through use of pyranose oxidase (PROD: EC 1.1.3.10), glucokinase (EC 2.7.1.2), and an ATP-regenerating system. In a previous report (Clin Chem 1989;35:2039-43) the glucose interfering with the measurement of 1,5-AG was remov...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-11-01 00:00:00
abstract::Using Syva "EMIT" reagents and the Cobas Bio centrifugal analyzer, we have developed cost-effective assays for therapeutic drug monitoring of carbamazepine, phenobarbital, and phenytoin. With these optimized methods one can assay up to 2470 samples with a single 100-test EMIT kit with good precision and accuracy. Betw...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-08-01 00:00:00
abstract:BACKGROUND:Variability among assays used to measure intact parathyroid hormone (iPTH) is of particular concern because of the routine use of iPTH assay results to guide management of osteodystrophy and calcium metabolism in patients with end-stage renal disease (ESRD). The aim of this study was to determine the extent ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.071589
更新日期:2006-09-01 00:00:00
abstract:BACKGROUND:False-positive results are a common problem in real-time PCR identification of DNA sequences that differ from near neighbors by a single-nucleotide polymorphism (SNP) or deletion. Because of a lack of sufficient probe specificity, post-PCR analysis, such as a melting curve, is often required for mutation dif...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.091488
更新日期:2007-12-01 00:00:00
abstract:BACKGROUND:Little is known about trace metal alterations in the bones of dialysis patients or whether particular types of renal osteodystrophy are associated with either increased or decreased skeletal concentrations of trace elements. Because these patients are at risk for alterations of trace elements as well as for ...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:
更新日期:1999-09-01 00:00:00
abstract::This communication describes and evaluates an improved routine methodology for quantitating clinical proteinuria. Based on investigations of Piscator and of Savory et al., a modified Tsuchiya's reagent (ethanolic HCI-phosphotungstic acid) is used to precipitate proteins at 56 degrees C, followed by biuret spectrophoto...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-03-01 00:00:00
abstract:BACKGROUND:Recent use of Bacillus anthracis spores as a bioweapon has highlighted the need for a continuous monitoring system. Current monitoring systems rely on antibody-derived probes, which are not hardy enough to withstand long-term use under extreme conditions. We describe new, phage-derived probes that can be use...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.038018
更新日期:2004-10-01 00:00:00
abstract::Taurine was measured in cerebrospinal fluid by reacting it with fluorescamine to form a fluorescent derivative, followed by separation on a reversed-phase column and fluorometric detection and evaluation. The assay is rapid (17 min) and sensitive to as little as 1 mumol/L. The mean value for 27 cerebrospinal fluid sam...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-08-01 00:00:00
abstract::To determine the molar absorptivities of beta-NADH and beta-NAD at 260 nm, we purified the reduced form of the coenzyme by repeated anion-exchange chromatography. A NADH preparation was so obtained for which the 260 nm/340 nm absorbance ratio was 2.265. When calculated with epsilon 340 beta-NADH = 6.22 times 10-3 for ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-06-01 00:00:00
abstract:BACKGROUND:Meconium analysis is a diagnostically sensitive and objective alternative to maternal self-report for detecting prenatal tobacco exposure. Nicotine and metabolite disposition in meconium is poorly characterized, and correlation of analytes' concentrations with neonatal outcomes is unexplored. Our objectives ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.109173
更新日期:2008-12-01 00:00:00
abstract::We describe an enzyme-linked immunosorbent assay for determination of light-chain ratios for IgG, IgA, and IgM in serum. A commercial serum with known overall kappa and lambda concentrations was used as standard. To capture the respective immunoglobulins, we used antibodies to gamma, lambda and mu chains coated onto m...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-03-01 00:00:00