Abstract:
:The location of the Reference Value for an analyte within the population distribution affects the magnitude of error due to methodological bias. Using the gaussian distribution, we evaluated the effects of systematic and proportional biases of the method (positive and negative), mean value, and standard deviation on the magnitude of error. We chose four Reference Values for cholesterol as a model. For a population with a mean of 2.0 and SD of 0.36 g of cholesterol per liter, a 3% positive proportional bias causes sixfold more error at the 50th percentile than at the 97.5th. In general, the error for a given bias (proportional or systematic) is greater for a Reference Value within the body than at the tails of the distribution. Further, the magnitude of the error varies as a function of the mean and standard deviation of the population.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Kroll MH,Ruddel M,Elin RJsubject
Has Abstractpub_date
1988-11-01 00:00:00pages
2256-9issue
11eissn
0009-9147issn
1530-8561journal_volume
34pub_type
杂志文章abstract::We describe a simple, highly reproducible kinetic technique for precisely measuring temperature in spectrophotometric systems having reaction cells that are inaccessible to conventional temperature probes. The method is based on the temperature dependence of pseudo-first-order rate constants for the acid-catalyzed hyd...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-05-01 00:00:00
abstract::We describe a rapid, precise, and sensitive radiometric assay for human lactoferrin. In this typical "sandwich"-type assay, anti-human lactoferrin is adsorbed onto a polystyrene sphere and bound lactoferrin is detected by the subsequent binding of 125I-labeled anti-human lactoferrin. The assay is accurate for lactofer...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-03-01 00:00:00
abstract:BACKGROUND:We explored the utility of multiplexed temperature gradient capillary electrophoresis (TGCE) as a screening tool for identifying genetic changes in the human mitochondrial genome. We examined changes in mitochondrial DNA (mtDNA) in nonmelanoma skin cancers (NMSCs), using TGCE to resolve genetic differences c...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.040311
更新日期:2005-02-01 00:00:00
abstract::This one-dimensional thin-layer chromatographic method is used for assay of phospholipids in the gastric aspirate of newborns. The solvent mixture (chloroform/hexane/methanol/glacial acetic acid/water, 12/7/4/3/0.3 by vol) completely resolves lecithin, sphingomyelin, phosphatidylinositol, phosphatidylserine, phosphati...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-04-01 00:00:00
abstract::We describe the performance of an RIA for the measurement of prostate-specific antigen (PA). Between-assay precision (CV) for control sera with various analyte concentrations was as follows: mean = 1.67 micrograms/L, CV = 7.1%; mean = 4.47 micrograms/L, CV = 5.6%; mean = 7.15 micrograms/L, CV = 5.5% (n = 19 each). Ana...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-05-01 00:00:00
abstract:BACKGROUND:The time required for bloodstream pathogen detection, identification (ID), and antimicrobial susceptibility testing (AST) does not satisfy the acute needs of disease management. Conventional methods take up to 3 days for ID and AST. Molecular diagnostics have reduced times for ID, but their promise to suppla...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2018.290189
更新日期:2018-10-01 00:00:00
abstract::Detection of intracellular antigens by flow cytometry requires effective fixation and permeabilization of the cell membrane. This study compares three fixation/permeabilization techniques: two commercial chemical reagents, the ORTHOPermeaFix (OPF) and the FIX&PERM Cell Permeabilization Kit (F&P), and a novel method ba...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-11-01 00:00:00
abstract:INTRODUCTION:Parathyroid hormone-related peptide (PTHrP) is involved in activating pathways, allowing tumor cells to form bone metastases. Measurement of PTHrP is used for the diagnosis and clinical management of patients suspected of hypercalcemia of malignancy. We developed an LC-MS/MS method for measuring PTHrP, est...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2015.244012
更新日期:2016-01-01 00:00:00
abstract::Backpropagation neural networks are a computer-based pattern-recognition method that has been applied to the interpretation of clinical data. Unlike rule-based pattern recognition, backpropagation networks learn by being repetitively trained with examples of the patterns to be differentiated. We describe and analyze t...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章,随机对照试验
doi:
更新日期:1993-09-01 00:00:00
abstract:BACKGROUND:There have been no large-scale analyses of resource utilization comparing the overall costs to treat pediatric patients vs adult patients. Likewise, there have been no studies evaluating the costs of the various components of hospitalization (e.g., accommodation, laboratory, radiology, and drugs) among adult...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-01-01 00:00:00
abstract::We immunoenzymometrically measured creatine kinase (CK) isoenzyme MB in extracts of myocardium and in homogenates of five different skeletal muscles. CK-MB concentrations in the former averaged 80.9 micrograms/g wet tissue; in the skeletal muscles it varied widely, being (e.g.) 25-fold greater in diaphragm than in pso...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-02-01 00:00:00
abstract::Carbohydrate-deficient transferrin (CDT) may now be the most valuable biological marker for diagnosis of alcohol abuse. We compared the diagnostic performance of two new CDT tests, Axis %CDT turbidimetric immunoassay (TIA) and Axis %CDT HPLC, against Specialty Laboratories' isoelectric focusing/immunoblotting/laser de...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1997-06-01 00:00:00
abstract::The commonly used methods of assessing the precision of the automated leukocyte differential have certain drawbacks that affect the validity and comparability of results. In the present report, we introduce a procedure based on building precision profiles from a large number of within-run imprecision experiments. The ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-07-01 00:00:00
abstract::In this immunoenzymatic assay for human lutropin (hLH) we used bi-specific antibodies (BiAbs) obtained from the fusion of two hybridomas producing antibodies to beta-D-galactosidase and hLh. The BiAb complexed with the enzyme beta-D-galactosidase was used as tracer in a double-determinant assay. We compared the assay ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-01-01 00:00:00
abstract::In "flow-injection analysis," the sample is inserted into a stream of reagent by use of a sample-injection valve. Mixing occurs downstream from the valve in a coil of tubing. With chemiluminescence detection this coil is positioned in front of a photomultiplier. We have evaluated the system for detection of hydrogen p...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-09-01 00:00:00
abstract::We measured advanced glycosylation end products in the mesenteric artery of 37 patients (ages 29-82 years), 34 of whom were nondiabetic. Samples of arterial tissue were obtained during bowel resectioning. Advanced glycosylation end products were measured as collagen-linked fluorescence (excitation wavelength 370 nm, e...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-04-01 00:00:00
abstract::The objective of this study was to develop a clinical laboratory method for subclass typing of human immunoglobulin G (IgG) paraproteins. Serum proteins were isoelectrically focused (IEF) in a mini-gel and passively blotted by capillary diffusion onto untreated nitrocellulose. Unreacted sites on the nitrocellulose wer...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-03-01 00:00:00
abstract::We used a modification of the polymerase chain reaction (PCR), involving two pairs of oligonucleotide primers, to detect a mutation in the low-density lipoprotein (LDL) receptor gene, commonly occurring among patients with familial hypercholesterolemia (FH) in Finland. This mutation, called FH-Helsinki, involves a lar...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-06-01 00:00:00
abstract::Adrenocortical causes of hypertension are established by examining the mineralocorticoid hormones produced in the zona glomerulosa and zona fasciculata. In the zona glomerulosa, aldosterone excess leads to hypertension, hypokalemia, and suppressed plasma renin activity, with increased concentrations of urinary aldoste...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1991-10-01 00:00:00
abstract:BACKGROUND:MALDI-TOF mass spectrometry (MS) is set to make inroads into clinical chemistry because it offers advantages over other analytical platforms. These advantages include low acquisition and operating costs, ease of use, ruggedness, and high throughput. When coupled with innovative front-end strategies and appli...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2015.239491
更新日期:2016-01-01 00:00:00
abstract::The S-peptide and S-protein fragments of ribonuclease S (RNase S, no EC no. assigned) have been immobilized onto separate Sepharose gels via a "leash" of polycytidylic acid substrate. Each of these gels releases its RNase fragment when treated with the complementary enzyme fragment or with RNase A (EC 3.1.27.5), and t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-09-01 00:00:00
abstract:BACKGROUND:Analysis of fetal DNA in maternal plasma has recently been introduced as a new method for noninvasive prenatal diagnosis, particularly for the analysis of fetal genetic traits, which are absent from the maternal genome, e.g., RHD or Y-chromosome-specific sequences. To date, the analysis of other fetal geneti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2003.029835
更新日期:2004-06-01 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::We examined the variability of lipid and lipoprotein concentrations in plasma from a population sample from the Jerusalem Lipid Research Clinic study. Coefficients of variation of about 8% for plasma cholesterol, 11% to 15% for low- and high-density-lipoprotein cholesterol, and about 30% for triglyceride were reported...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-07-01 00:00:00
abstract:BACKGROUND:Reliable detection of neuroblastoma cells in bone marrow (BM) is critical because BM involvement influences staging, risk assessment, and evaluation of therapeutic response in neuroblastoma patients. Standard cytomorphologic examination of BM aspirates is sensitive enough to detect single tumor cells. Conseq...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.059485
更新日期:2006-03-01 00:00:00
abstract::We compared different sample-handling techniques for measurement of Na+ and K+ with ion-selective electrodes (ISE). Imprecision was less for venous blood (with a minimum of heparin) than for plasma, serum, or capillary blood. The results for K+ were higher for serum than for whole blood, and higher for whole blood tha...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-03-01 00:00:00
abstract:BACKGROUND:The current diagnosis and monitoring of bladder cancer are heavily reliant on cystoscopy, an invasive and costly procedure. Previous efforts in urine-based detection of bladder cancer focused on targeted approaches that are predicated on the tumor expressing specific aberrations. We aimed to noninvasively de...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2018.301341
更新日期:2019-07-01 00:00:00
abstract::Gene mutations responsible for the majority of Duchenne/Becker muscular dystrophy (DMD/BMD) and cystic fibrosis (CF) chromosomes have been identified. We describe a DNA-based strategy, rather than the traditional biochemical assays, for screening newborns. DNA sequences spanning the CF mutation and several DMD/BMD del...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-10-01 00:00:00
abstract::The kidney and its response to the antidiuretic hormone (ADH) are the principal protective mechanisms necessary to maintain a normal plasma tonicity (osmolality). Hence, determination of the response of the ADH-renal axis to an abnormal plasma tonicity is an important step to understanding water homeostasis. Determina...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1994-07-01 00:00:00
abstract::Major depression is one of the most common clinical problems seen by primary-care physicians. The prevalence is 5% to 10% in primary-care outpatients and 15% in medically ill inpatients. Despite this high prevalence rate, depression is frequently not accurately diagnosed. Evidence suggests that misdiagnosis often occu...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1988-05-01 00:00:00