Abstract:
RATIONALE AND OBJECTIVES:Several methods have been proposed for estimating the standard error (SE) of the area under the curve (AUC) in receiver operating characteristic analysis. The authors examined the validity of three methods--the LABROC procedure, exponential approximation, and the method of DeLong et al (purely nonparametric)--for estimating the SE of the AUC in receiver operating characteristic analysis of quantitative diagnostic data. MATERIALS AND METHODS:The authors conducted a broad numerical investigation to assess how to estimate the SE of AUC in various configurations of binormal and nonbinormal pairs of distributions, in which one or both pair members were mixtures of Gaussian distributions (the samples included 100 in the diseased group and 100 in the nondiseased group). RESULTS:The authors found that exponential approximation of the SE of AUC slightly underestimates the observed SE of a nonparametric estimate of the AUC when the ratio of the standard deviation of distributions for diseased to nondiseased populations was greater than 2. With binormal data the observed SE tended to be smaller with the LABROC procedure (semiparametric) than with the method of DeLong et al, but the LABROC procedure yields more conservative estimates of SE with nonbinormal data. In particular, with bimodal data it often produces a more conservative (ie, larger) estimate of the actual (observed) fluctuation. CONCLUSION:Overall, the LABROC procedure and the method of DeLong et al yielded very close estimates of the SE of AUC, even with data generated from a nonbinormal model. The choice between these two methods can be based on users' preferences and practicality.
journal_name
Acad Radioljournal_title
Academic radiologyauthors
Hajian-Tilaki KO,Hanley JAdoi
10.1016/s1076-6332(03)80561-5keywords:
subject
Has Abstractpub_date
2002-11-01 00:00:00pages
1278-85issue
11eissn
1076-6332issn
1878-4046journal_volume
9pub_type
杂志文章abstract:RATIONALE AND OBJECTIVES:To investigate changes in lung microstructure in healthy adult subjects with no smoking history using diffusion-weighted 3He MRI. MATERIALS AND METHODS:Diffusion magnetic resonance imaging using hyperpolarized helium 3 (3He) was applied to healthy volunteers to explore the dependence of lung m...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2005.08.005
更新日期:2005-11-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Computed tomography (CT) airways measurements can be used as surrogates to spirometric measurements for assessing bronchodilation in a particular patient with chronic obstructive pulmonary disease. Although spirometric measurements show variations within the opening hours of a hospital departme...
journal_title:Academic radiology
pub_type: 杂志文章
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更新日期:2018-12-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Cellulitis is a common cause for emergency department (ED) presentation and subsequent hospital admission. Underlying fracture, osteomyelitis, or foreign body is often considered in the clinical evaluation of these patients. Accordingly, plain radiographs (XRs) of the affected extremity are oft...
journal_title:Academic radiology
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更新日期:2015-11-01 00:00:00
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journal_title:Academic radiology
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更新日期:1996-01-01 00:00:00
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journal_title:Academic radiology
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abstract:RATIONALE AND OBJECTIVES:To evaluate clinical and imaging features associated with adequacy of the hepatocyte phase (HP) in gadoxetate disodium-enhanced liver magnetic resonance imaging (MRI) in patients without chronic liver disease (CLD). MATERIALS AND METHODS:This was a retrospective institutional review board-appr...
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journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2020.05.038
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journal_title:Academic radiology
pub_type: 杂志文章
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journal_title:Academic radiology
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journal_title:Academic radiology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.acra.2005.11.006
更新日期:2006-03-01 00:00:00
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更新日期:2021-01-04 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/s1076-6332(03)80297-0
更新日期:2002-01-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2020.12.005
更新日期:2020-12-15 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2012.09.025
更新日期:2013-03-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章,多中心研究
doi:10.1016/S1076-6332(03)80535-4
更新日期:2001-03-01 00:00:00
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更新日期:2010-02-01 00:00:00
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更新日期:2013-11-01 00:00:00
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journal_title:Academic radiology
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更新日期:2014-04-01 00:00:00
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更新日期:2012-01-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章,评审
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更新日期:1995-04-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2011.10.022
更新日期:2012-03-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2016.06.004
更新日期:2016-10-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2012.05.013
更新日期:2012-10-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
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更新日期:2019-07-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
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更新日期:2020-05-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
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更新日期:2012-06-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
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更新日期:2020-01-01 00:00:00
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journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2004.11.015
更新日期:2005-03-01 00:00:00