Grant Number:	2R01CA076031-04 Interpret this number
Primary Investigator:	Piegorsch, Walter
Organization:	University Of South Carolina At Columbia
Project Title:	Low Dose Risk Bounds Via Simultaneous Confidence Bands
Fiscal Year:	2000

DESCRIPTION (Adapted from applicant's abstract): Quantifying environmental and other detrimental risks from exposure to hazardous agents is an important component in the process of risk evaluation and assessment. The primary goal of this project is to extend and study statistical confidence bands for use in low-dose risk extrapolation. Application is directed to environmental and occupational risk assessment studies where human or animal data are used to set benchmark or other safe low-dose levels of a hazardous agent, but where study information is limited to high dose levels of the agent. Methods are considered for estimating upper confidence limits on predicted risk for various endpoints measured on both continuous and discrete scales. From the simultaneous confidence bounds, lower confidence limits on the benchmark dose (BMD) associated with a particular risk are calculated. An important feature of the simultaneous construction is that any inferences based on inverting the simultaneous confidence bounds apply automatically to inverse bounds on the BMD. The methodology extends previous results for simultaneous confidence bands to normally and non-normally distributed data with dose-dependent variance models, and to higher-dimensional parameter spaces associated with non-linear dose-response functions. An evaluation phase of the project studies the small-sample operating characteristics of the new methodology via Monte Carlo computer calculations, and applies the new methods to existing data for a number of endpoints encountered in quantitative risk assessment/low-dose extrapolation problems. The new methods fill existing gaps in low-dose risk extrapolation, and have application to a wide variety of data-analytic scenarios in quantitative risk assessment.




Confidence Limits On One-stage Model Parameters In Benchmark Risk Assessment
Authors: Buckley B.E. , Piegorsch W.W. , West R.W. .
Source: Environmental And Ecological Statistics, 2009-03-01 00:00:00.0; 16(1), p. 53-62.
PMID: 20160851
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Bootstrap Methods For Simultaneous Benchmark Analysis With Quantal Response Data
Authors: West R.W. , Nitcheva D.K. , Piegorsch W.W. .
Source: Environmental And Ecological Statistics, 2009-03-01 00:00:00.0; 16(1), p. 63-73.
PMID: 20160852
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Simultaneous Confidence Bands For Abbott-adjusted Quantal Response Models
Authors: Buckley B.E. , Piegorsch W.W. .
Source: Statistical Methodology, 2008 May; 5(3), p. 209-219.
PMID: 19412325
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Communicating The Risks, And The Benefits, Of Nanotechnology
Authors: Piegorsch W.W. , Schuler E. .
Source: International Journal Of Risk Assessment And Management, 2008-01-01 00:00:00.0; 10(1-2), p. 57-69.
PMID: 19823594
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Benchmark Analysis For Quantifying Urban Vulnerability To Terrorist Incidents
Authors: Piegorsch W.W. , Cutter S.L. , Hardisty F. .
Source: Risk Analysis : An Official Publication Of The Society For Risk Analysis, 2007 Dec; 27(6), p. 1411-25.
PMID: 18093043
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On Use Of The Multistage Dose-response Model For Assessing Laboratory Animal Carcinogenicity
Authors: Nitcheva D.K. , Piegorsch W.W. , West R.W. .
Source: Regulatory Toxicology And Pharmacology : Rtp, 2007 Jul; 48(2), p. 135-47.
PMID: 17490794
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Benchmark Analysis: Shopping With Proper Confidence
Authors: Piegorsch,W.W. , West,R.W. .
Source: Risk Analysis : An Official Publication Of The Society For Risk Analysis, 2005 Aug; 25(4), p. 913-20.
PMID: 16268938
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Multiplicity-adjusted Inferences In Risk Assessment: Benchmark Analysis With Quantal Response Data
Authors: Nitcheva D.K. , Piegorsch W.W. , West R.W. , Kodell R.L. .
Source: Biometrics, 2005 Mar; 61(1), p. 277-86.
PMID: 15737104
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Simultaneous Confidence Bounds For Low-dose Risk Assessment With Nonquantal Data
Authors: Piegorsch W.W. , West R.W. , Pan W. , Kodell R.L. .
Source: Journal Of Biopharmaceutical Statistics, 2005; 15(1), p. 17-31.
PMID: 15702602
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Confidence Bands For Low-dose Risk Estimation With Quantal Response Data
Authors: Al-Saidy O.M. , Piegorsch W.W. , West R.W. , Nitcheva D.K. .
Source: Biometrics, 2003 Dec; 59(4), p. 1056-62.
PMID: 14969485
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On A Likelihood-based Goodness-of-fit Test Of The Beta-binomial Model
Authors: Garren S.T. , Smith R.L. , Piegorsch W.W. .
Source: Biometrics, 2000 Sep; 56(3), p. 947-50.
PMID: 10985242
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Estimation And Testing With Overdispersed Proportions Using The Beta-logistic Regression Model Of Heckman And Willis
Authors: Slaton T.L. , Piegorsch W.W. , Durham S.D. .
Source: Biometrics, 2000 Mar; 56(1), p. 125-33.
PMID: 10783786
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