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 QC events and leaving large gaps of time when control samples are never run, yet patient samples are being tested. METHODS:Mathematical derivations and computer simulation were used to determine the expected waiting time between an out-of-control condition and the next scheduled QC test for various QC testing strategies that use fixed or random intervals between QC tests. RESULTS:Scheduling QC tests at fixed intervals yields an average time between the occurrence of an out-of-control error condition and the next scheduled QC test that is equal to half of the fixed time interval. This performance was the best among the QC scheduling strategies investigated. Near-optimal performance, however, was achieved by randomly selecting time intervals between QC events centered on the desired expected interval length, a method that provides variation in QC testing times throughout the day. CONCLUSIONS:If the goal is to vary QC testing times throughout the day while maintaining the shortest expected length of time between error conditions and the next scheduled QC test, then a near-optimal QC scheduling strategy combines randomly selected time intervals centered on the desired length of time between QC events with fixed time intervals.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Parvin CA,Robbins S 3rddoi
10.1373/clinchem.2006.083311subject
Has Abstractpub_date
2007-04-01 00:00:00pages
575-80issue
4eissn
0009-9147issn
1530-8561pii
clinchem.2006.083311journal_volume
53pub_type
杂志文章abstract：BACKGROUND:Mass spectrometric assays could potentially replace protein immunoassays in many applications. Previous studies have demonstrated the utility of liquid chromatography-multiple-reaction monitoring-mass spectrometry (LC-MRM/MS) for the quantification of proteins in biological samples, and many examples of the ...
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abstract：BACKGROUND:The liver is frequently subject to insult because of viral infection, alcohol abuse, or toxic chemical exposure. Extensive research has been conducted to identify blood markers that can better discern liver damage, but little progress has been achieved in clinical practice. Recently, circulating microRNAs (m...
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doi：10.1373/clinchem.2010.147850
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abstract：:We describe a micro-scale method for determining serum theophylline. The chromatography system includes a muBondapack C18 column and acetonitrile, 70 ml/liter of sodium acetate buffer (10 mmol/liter, ph 4.0) as the mobile phase. Test serum or plasma, 30 mul, is mixed with an equal quantity of a solution containing the...
journal_title：Clinical chemistry
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doi：
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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 estimate...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-07-01 00:00:00
abstract：:In this rapid, cost-effective, enzyme-linked immunosorbent assay for 17 alpha-hydroxyprogesterone (17-OHP) eluted from dried blood spotted on filter paper, second antibody is coated onto the microwell plate and horseradish peroxidase (EC 1.11.1.7) is the label enzyme. Antiserum to 17-OHP was prepared by using 4-(2-car...
journal_title：Clinical chemistry
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doi：
更新日期：1987-06-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-02-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-11-01 00:00:00
abstract：:Imferon (Merrell-National), an iron-dextran complex, is widely used in patients with iron deficiency. It is present in the circulation in appreciable amounts for two to three weeks after administration and interferes with all tested colorimetric iron assays, both with and without deproteinization. The amount of the pl...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-04-01 00:00:00
abstract：BACKGROUND:Cerebrospinal fluid (CSF) tau is a common biomarker for Alzheimer disease (AD). Measurements of tau have historically been performed using immunoassays. Given the molecular diversity of tau in CSF, the selectivity of these immunoassays has often been questioned. Therefore, we aimed to develop an analytically...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.216515
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journal_title：Clinical chemistry
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更新日期：2012-02-01 00:00:00
abstract：:We compared a chemiluminescent assay and a colorimetric endpoint assay for measuring an alkaline phosphatase (EC 3.1.3.1) label in an enzyme immunoassay of thyrotropin (TSH). The substrate in the chemiluminescent assay is a derivative of adamantyl 1,2-dioxetane phosphate. On dephosphorylation, catalyzed by alkaline ph...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-07-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-01-01 00:00:00
abstract：BACKGROUND:Adequate detection of designer steroids in the urine of athletes is still a challenge in doping control analysis and requires knowledge of steroid metabolism. In this study we investigated whether uPA(+/+)-SCID mice carrying functional primary human hepatocytes in their liver would provide a suitable alterna...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.119396
更新日期：2009-10-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-03-01 00:00:00
abstract：BACKGROUND:Increased cardiac troponin concentrations in acute coronary syndrome (ACS) identify patients with ongoing cardiomyocyte necrosis who are at increased risk. However, with the use of more precise assays, cardiac troponin increases are commonly noted in other cardiovascular conditions as well. This has generate...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2016.261495
更新日期：2017-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-04-01 00:00:00
abstract：:A direct mehtod [Clin. Chim. Acta 46, 113 (1973)] for determination of inorganic phosphate in serum was adapted for use with a centrifugal analyzer. Contamination is minimized and analysis rate maximized by doing the reaction in the reagent wells of the transfer disc and by utilizing the high-speed spectrophotometric ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-02-01 00:00:00
abstract：:The formal definition of sensitivity associates the term with the change in the response of a system for a small change of the stimulus causing the response, i.e., the ratio of the response of a system to the stimulus causing it. One interpretation of sensitivity associates the rate of change of the response for a sma...
journal_title：Clinical chemistry
pub_type： 评论,杂志文章
doi：
更新日期：1997-10-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1998-07-01 00:00:00
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journal_title：Clinical chemistry
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doi：10.1373/clinchem.2013.219378
更新日期：2014-06-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-05-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1984-12-01 00:00:00
abstract：:A triclonal gammopathy is an immunoglobulin abnormality in which three discrete monoclonal subpopulations of immunoglobulin molecules are present in a patient's serum. Monoclonal and biclonal gammopathies have been studied extensively, but relatively little is known about the much rarer triclonal gammopathies. The cas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：:Numerous outcome measures can be used to characterize and compare the performance of alternative quality-control (QC) strategies. The performance measure traditionally used in the QC planning process is the probability of rejecting an analytical run when a critical out-of-control error condition exists. Another perfor...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-04-01 00:00:00
abstract：:We conducted a proficiency survey of cholesterol and high-density lipoprotein (HDL) cholesterol analysis in local clinical laboratories to determine whether increased national emphasis on cholesterol measurement had resulted in changes in performance from previous surveys. Sets of frozen aliquots of plasma and HDL sup...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-08-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-12-01 00:00:00
abstract：BACKGROUND:Lysosomal storage disorders (LSDs) comprise more than 40 genetic diseases that result in the accumulation of products that would normally be degraded by lysosomal enzymes. A tandem mass spectrometry (MS/MS)-based method is available for newborn screening for 5 LSDs, and many laboratories are initiating pilot...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.111864
更新日期：2009-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.099424
更新日期：2008-07-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章,评审
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更新日期：2012-01-01 00:00:00
