Abstract:
:Published estimates of the imprecision characteristics of immunoassays are often based on quantities of data that seem to be inadequate. The increasing use of imprecision profiles has not necessarily improved the situation. We describe and illustrate a method of computing 95% confidence intervals for profiles estimated directly from replicated assay results. The data used were chosen to mimic the sort of data that are typically available in practice, either within laboratories or from external quality-assessment programs. Use of confidence intervals is an effective pictorial way of incorporating information about the quantity and the distribution of the data used for estimation. This is in keeping with an important property of imprecision profile plots: potentially complex information is summarized in a readily comprehensible way. A computer program is available for estimating and plotting profiles and their 95% confidence intervals.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Sadler WA,Smith MHsubject
Has Abstractpub_date
1990-07-01 00:00:00pages
1346-50issue
7eissn
0009-9147issn
1530-8561journal_volume
36pub_type
杂志文章abstract:BACKGROUND:Age-adjusted morbidity and mortality rates from coronary heart disease (CHD) are higher in men than in women. Androgens are suspected to be responsible for the male disadvantage. The genomic effect of androgens is mediated by the androgen receptor (AR), which has a polymorphic CAG repeat in exon 1. The numbe...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:10.1373/clinchem.2005.049262
更新日期:2005-07-01 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::We report the intermediate-term effects of three consecutive evenings of moderate ethanol ingestion (0.75 g/kg body weight each evening) on activity values for alkaline phosphatase, gamma-glutamyltransferase, creatine kinase, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase in sera of ni...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-05-01 00:00:00
abstract::In this automated system for assaying guanidino compounds, the compounds are resolved on an ion-exchange (Dowex 50) column, then reacted with phenanthrenequinone in alkaline solution. This mixture is then acidified and the resulting fluorescence is measured (lambda ex, 305 nm; lambda em, 395 nm). I applied the system ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-02-01 00:00:00
abstract:BACKGROUND:Stability of chemical speciation during sample handling and storage is a prerequisite to obtaining reliable results of trace element speciation analysis. There is no comprehensive information on the stability of common arsenic species, such as inorganic arsenite [As(III)], arsenate [As(V)], monomethylarsonic...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract:BACKGROUND:Patients differ in responses to warfarin, which is commonly prescribed to treat thromboembolic events. Genetic variations in the cytochrome P450, family 2, subfamily C, polypeptide 9 (CYP2C9), vitamin K epoxide reductase complex, subunit 1 (VKORC1), and gamma-glutamyl carboxylase (GGCX) genes have been shown...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.118497
更新日期:2009-04-01 00:00:00
abstract::We determined approximately 15,000 laboratory values in 236 individuals between the ages of 60 and 90 y, 22 individuals between 90 and 99 y, and 69 individuals greater than or equal to 100 y, and compared these with values in young adults. We tested 47 different analytes in the 60-90-y group and 93 analytes in the gre...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-06-01 00:00:00
abstract::Numerous papers have been written to show which combinations of Shewhart-type quality-control charts are optimal for detecting systematic shifts in the mean response of a process, increases in the random error of a process, and linear drift effects in the mean response across the assay batch. One paper by Westgard et ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-08-01 00:00:00
abstract:BACKGROUND:Functional antibody surfaces were prepared on ultraflat polystyrene surfaces by physical adsorption, and the uniform distribution of monoclonal antibodies against hepatitis B surface antigen (anti-HBs) on such surfaces and the presence of dense hepatitis B surface antigen (HBsAg) particles captured by immobi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2000-09-01 00:00:00
abstract:BACKGROUND:The purpose of this study was to assess the feasibility of infrared (IR) spectroscopy for the simultaneous quantification of serum LDL-cholesterol (LDL-C) and HDL-cholesterol (HDL-C) concentrations. METHODS:Serum samples (n = 90) were obtained. Duplicate aliquots (5 microL) of the serum specimens were dried...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-03-01 00:00:00
abstract::We report the measure of prostate-specific antigen (PSA) from extracts of blood dried on filter paper. Five 3-mm (diameter) paper discs containing approximately 25 microL of dried whole blood were punched from the filter paper and extracted with 500 microL of buffer. Recovery of PSA was > 92%. Imprecision of the filte...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-04-01 00:00:00
abstract::We describe a rapid polarization fluoroimmunoassay for screening for the presence of barbiturates in urine. The single reagent is prepared by pre-mixing antiserum with a fluorescein-labeled barbiturate derivative as tracer. Use of a mixture of two sheep antisera, raised against different barbiturate immunogens, result...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-11-01 00:00:00
abstract:BACKGROUND:Measurement of plasma renin is important for the clinical assessment of hypertensive patients. The most common methods for measuring plasma renin are the plasma renin activity (PRA) assay and the renin immunoassay. The clinical application of renin inhibitor therapy has thrown into focus the differences in i...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2008.118000
更新日期:2009-05-01 00:00:00
abstract::We report the first solid-phase radioimmunoassay for triiodothyronine with use of antibody-coated tubes, which is designed specifically for the fully automated radioimmunoassay instrument, Micromedic Systems' "Concept 4 Automatic Radioassay." Antisera to triiodothyropropionic acid/bovine serum albumin were raised in r...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-05-01 00:00:00
abstract::We evaluated the Hybritech Tandem-E procedure for quantifying choriogonadotropin (hCG) in human serum. In this "sandwich"-type assay, two monoclonal antibodies directed against different regions of the hCG molecule are used, one coated on a plastic bead, the second conjugated to alkaline phosphatase. The assay can det...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-03-01 00:00:00
abstract::The human ras gene plays a fundamental role in the transduction of extracellular signals to the nucleus, thereby regulating cell growth and differentiation. Point mutations in the ras gene convert it into a transforming oncogene that has been found in many solid and hematologic malignancies. We describe a rapid and se...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-05-01 00:00:00
abstract::We describe a system for detection of leukemia cells involving complement-mediated cytotoxic reaction and an image processing system, consisting of a charge-coupled-device image sensor, an image memory board, a personal computer, and a phase-contrast microscope. Then added to a cell suspension, monoclonal antibody spe...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-04-01 00:00:00
abstract::Owing to increased enzymatic hydrolysis of glutamine, additional ammonia is formed in blood and plasma specimens with increased gamma-glutamyltransferase activity (gamma-GT, EC 2.3.2.2.). The close correlation between gamma-GT and glutaminase (EC 3.5.1.2) activities (r = 0.97) in plasma, the inhibition with 6-diazo-5-...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-08-01 00:00:00
abstract::We developed a novel noncompetitive immunoassay format for monoepitopic analytes and describe here a model assay for triiodothyronine (T3), performed on Ciba Corning's ACS:180 analyzer. Acridinium ester (AE)-labeled bivalent anti-T3 was incubated with the sample, producing AE-anti-T3/T3 complexes and unreacted AE-anti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-07-01 00:00:00
abstract:BACKGROUND:Insulin, growth hormone (GH), and growth factors (insulin-like growth factors [IGFs] and their binding proteins [IGFBPs]) are known to influence fetal growth and also the synthesis/secretion of the recently discovered hormones leptin and ghrelin. METHODS:In 153 delivering mothers and their offspring at birt...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.095299
更新日期:2008-03-01 00:00:00
abstract::Concentrations of triglycerides are increased and concentrations of high-density lipoprotein (HDL) cholesterol are low in women with hyperandrogenism. These alterations could be related to excessive androgen or estrogen, to hyperinsulinism, or to a combination of these abnormalities. We examined their independent infl...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-02-01 00:00:00
abstract::We divided patients with brain lesions into three groups: (a) patients with primary or metastatic brain cancer, (b) brain infarctions, and (c) brain contusion(s). We analyzed each patient's sera for creatine kinase isoenzyme BB (CK-BB), using a monoclonal antibody kit (Impres-BB; International Immunoassay Laboratories...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-04-01 00:00:00
abstract::A modified fermentation procedure based on one described by Homer Smith in his textbook was used to eliminate glucose interference in the automated detrmination of inulin. The manifold of Fjeldbo and Stamey [J. Lab. Clin. Med. 72, 353 (1968)] was modified to enable us to insert the fermentation procedure without sacri...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-07-01 00:00:00
abstract:BACKGROUND:Quantification of 5-hydroxyindole-3-acetic acid (5-HIAA) in urine is useful in diagnosing and monitoring of patients with carcinoid tumors and in the study of serotonin (5-hydroxytryptamine) metabolism in various disorders. We describe an automated method that incorporates on-line solid-phase extraction (SPE...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.050062
更新日期:2005-09-01 00:00:00
abstract::A novel noninstrumented technology (ChemTrak AccuMeter) for the quantitative measurement of analytes in biological fluids was reported at the 1990 Oak Ridge Conference (Clin Chem 1990;36:1591-7). This instrument-free technology has been adapted for the quantitative measurement of high-density lipoprotein (HDL). An in ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-09-01 00:00:00
abstract::We report the accuracy, imprecision, total analytical errors, and patient misclassification errors for cholesterol measured from capillary whole blood, venous whole blood, and venous plasma samples by five devices used in public cholesterol screening environments: Reflotron, Vision, Ektachem DT-60, QuickRead, and Lipo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-02-01 00:00:00
abstract::Two-dimensional electroimmunodiffusion is rarely used in clinical chemistry, because its potentialities are not yet widely appreciated. Studying mouse anaphylaxis, we observed with this technique certain striking short- and long-term pathologic changes in several important serum antigens, which aptly demonstrate its u...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-05-01 00:00:00
abstract::We measured thyroid hormones and thyroxin-binding proteins in serum from 62 normal lactating and 52 nonlactating women at three months postpartum, and compared these values with those for 42 nonpregnant control women of similar age. Mean thyroxin concentrations in the lactating and nonlactating women were significantl...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-07-01 00:00:00
abstract:BACKGROUND:Efforts to reduce the high global prevalence of nutritional anemia require the use of both reliable laboratory assays to distinguish iron deficiency from other causes of anemia and cost-effective methods for collection of blood specimens under field conditions. The suitability of using small plasma samples s...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1999-10-01 00:00:00
abstract:BACKGROUND:In vitro and animal studies suggest that tumor necrosis factor alpha (TNF-alpha) modulates intestinal iron transport. We hypothesized that the effect of TNF-alpha might be particularly relevant if iron absorption is not effectively controlled by the HFE gene. METHODS:In patients with homozygous C282Y hemoch...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.065417
更新日期:2006-08-01 00:00:00