This is a Mentored Quantitative Research Career Development Award Application to gain comprehensive understanding of clinical and biological correlates of Alzheimer's disease (AD) and to assess the statistical applications and the quality of longitudinal statistical methodologies in AD publications over time. The training goals, which will be met through an active mentored research project as well as formal course work, seminars, workshops, and participation in ADRC clinical/cognitive assessments, are threefold: (1) to enhance my knowledge in the area of AD research in general, (2) to receive training in the collection, management, analysis of AD research data, and (3) to understand and assess which, and how quantitative methodologies have been used in AD studies.
The specific aims of the research project are: (1) to characterize the trend over time on the use of statistical designs and methodologies in AD research, the way statistical analyses were reported, and the types of statistical analyses were reported, and the types of statistical packages used in AD publications, (2) to develop an instrument to assess the quality of statistical methodologies in published longitudinal AD studies, (3) to identify less-than-optimal uses of statistics in published longitudinal AD studies, (4) to assess the role of biostatisticians/epidemiologists in published longitudinal AD Studies, and (5) to assess whether attenuation or absence of learning effects over time from psychometric tests differentiates individuals with preclinical AD from nondemented individuals without AD neuropathology, and to compare longitudinal statistical methodologies and demonstrate the consequences of less-than-optimal statistics in the analyses. Data from756 original research articles since 1984 will be reviewed to address Specific Aim 1 - 4, which will provide not only the first ever systematic and critical evaluation of statistics in AD publications, but also guidance on how the application of statistics can be improved in the future.
Specific Aim 5 will not only test an important hypothesis about the predictors of preclinical AD from WU ADRC database bust also provide a comparison of longitudinal statistical methods and demonstrate the inferential consequences when less-than-optimal statistics are used in the test of the hypothesis. These investigations will yield substantive contributions related to the statistical methodologies of AD research and help the 'translational' process disseminating advanced longitudinal statistical methodologies to research in AD Field.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Mentored Quantitative Research Career Development Award (K25)
Project #
5K25AG025189-03
Application #
7247858
Study Section
National Institute on Aging Initial Review Group (NIA)
Program Officer
Silverberg, Nina B
Project Start
2005-09-01
Project End
2009-06-30
Budget Start
2007-07-01
Budget End
2009-06-30
Support Year
3
Fiscal Year
2007
Total Cost
$110,820
Indirect Cost
Name
Washington University
Department
Biostatistics & Other Math Sci
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Xiong, Chengjie; van Belle, Gerald; Miller, J Philip et al. (2011) Designing clinical trials to test disease-modifying agents: application to the treatment trials of Alzheimer's disease. Clin Trials 8:15-26
Xiong, Chengjie; van Belle, Gerald; Zhu, Kejun et al. (2011) A Unified Approach of Meta-Analysis: Application to an Antecedent Biomarker Study in Alzheimer's Disease. J Appl Stat 38:15-27
Ances, B M; Christensen, J J; Teshome, M et al. (2010) Cognitively unimpaired HIV-positive subjects do not have increased 11C-PiB: a case-control study. Neurology 75:111-5
Xiong, Chengjie; Miller, J Philip; Morris, John C (2010) Measuring Study-Specific Heterogeneity in Meta-Analysis: Application to an Antecedent Biomarker Study of Alzheimer's Disease. Stat Biopharm Res 2:300-309
Xiong, Chengjie; Tang, Yuxiao; van Belle, Gerald et al. (2008) Evaluating the quality of longitudinal statistical applications in original publications on Alzheimer's disease. Neuroepidemiology 30:112-9
Xiong, Chengjie; Tang, Yuxiao; van Belle, Gerald et al. (2007) Assessing statistical applications in publications on Alzheimer's disease. Neuroepidemiology 28:235-45