Abstract:
:This paper discusses the application of repeated measures methods in the statistical analysis of an experiment in behavioral toxicology. The chronic marijuana smoke exposure study conducted at the National Center for Toxicological Research is used for an example of the types of problems that one encounters in analyzing these types of studies. In particular, the standard univariate analysis most frequently used for repeated measures analyses has some very restrictive assumptions on the form of the covariance matrices. These assumptions are not met in the example discussed and are rarely met in many other problems. Other possible models for analyzing repeated measures when these assumptions are not met are presented and discussed. Other problems specific to the chronic marijuana smoke exposure study that may occur in similar type studies are presented. These include pooling the experimental units into groups with comparable baselines, choosing a function of the measures to be analyzed, dealing with a large data set with many observation times and missing data, unequal group sizes and different designs for different subsets of the experimental animals. The standard univariate repeated measures analysis was chosen to analyze the data even though the violations of the covariance assumptions may lead to finding differences that do not exist (Type I or false-positive errors), since the other methods presented also had covariance assumptions that were not met or had low power. Use of Bonferroni-type multiple comparisons on the single degree of freedom contrasts of interest hopefully reduced the chances of these false-positive results.
journal_name
Neurotoxicol Teratoljournal_title
Neurotoxicology and teratologyauthors
Allen RR,Slikker W Jr,Paule MGdoi
10.1016/0892-0362(90)90005-wsubject
Has Abstractpub_date
1990-09-01 00:00:00pages
441-8issue
5eissn
0892-0362issn
1872-9738journal_volume
12pub_type
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
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journal_title:Neurotoxicology and teratology
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journal_title:Neurotoxicology and teratology
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doi:10.1016/0892-0362(88)90004-9
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journal_title:Neurotoxicology and teratology
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doi:10.1016/0892-0362(89)90084-6
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2007.08.001
更新日期:2007-11-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/s0892-0362(97)00094-9
更新日期:1998-07-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/s0892-0362(97)00135-9
更新日期:1998-09-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章,评审
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更新日期:2000-01-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2010.03.004
更新日期:2010-07-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2008.01.006
更新日期:2008-05-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/s0892-0362(01)00163-5
更新日期:2001-09-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2010.04.053
更新日期:2010-09-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2012.08.001
更新日期:2012-11-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2018.03.001
更新日期:2018-01-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2011.10.006
更新日期:2012-01-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2005.11.002
更新日期:2006-01-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2004.10.005
更新日期:2005-03-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2010.01.006
更新日期:2010-05-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/s0892-0362(96)00227-9
更新日期:1997-05-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/j.ntt.2010.10.001
更新日期:2011-03-01 00:00:00
abstract::Prenatal exposure to cocaine in rats has previously been shown to alter the behavioral and hormonal responses to acute stressors, although no work has yet examined stress adaptation in these animals in adulthood, a possibility examined in this experiment. Male and female offspring of Sprague-Dawley rat dams given 40 m...
journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/s0892-0362(00)00104-5
更新日期:2000-11-01 00:00:00
abstract::A long-term prospective cohort study was conducted to examine the association between prenatal and postnatal exposure to environmental lead and childhood neuropsychological development. The possible interactive effects of blood lead and some covariates on early development were explored in this study. Our data suggest...
journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/0892-0362(92)90038-c
更新日期:1992-09-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/s0892-0362(96)00226-7
更新日期:1997-03-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 临床试验,杂志文章
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更新日期:1999-01-01 00:00:00
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journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/s0892-0362(00)00094-5
更新日期:2000-09-01 00:00:00
abstract::The potential of emamectin benzoate (EB) to cause developmental neurotoxicity in Sprague-Dawley rats was assessed using a study design by the US EPA. Dosages of 0 (deionized water), 0.1, 0.6, or 3.6 mg/kg/day were administered at 5 ml/kg by oral gavage from gestational day (GD) 6 to lactational day (LD) 20 to groups o...
journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/s0892-0362(97)00002-0
更新日期:1997-07-01 00:00:00
abstract::Male Fischer 344 rats received either tap water or water containing 250 ppm lead for 90 days prior to training in either Pavlovian fear conditioning or consummatory contrast, an aversive reward reduction paradigm. In Experiment 1, lead-exposed and -unexposed rats were trained in operant chambers over a 6-min session. ...
journal_title:Neurotoxicology and teratology
pub_type: 杂志文章
doi:10.1016/s0892-0362(02)00265-9
更新日期:2002-07-01 00:00:00
abstract::Understanding the potentially harmful long term consequences of prenatal marijuana exposure is important given the increase in number of pregnant women smoking marijuana to relieve morning sickness. Altered executive functioning is one area of research that has suggested negative consequences of prenatal marijuana exp...
journal_title:Neurotoxicology and teratology
pub_type: 杂志文章,评审
doi:10.1016/j.ntt.2016.05.010
更新日期:2016-01-01 00:00:00