MRI substudy participation in alzheimer disease (AD) clinical trials: Baseline comparability of a substudy sample to entire study population

Rema Raman, Ronald G. Thomas, Michael W. Weiner, Clifford R Jr. Jack, Karin Ernstrom, Paul S. Aisen, Pierre N. Tariot, Joseph F. Quinn

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Objective: To determine if a self-selected group of participants who enroll in an imaging substudy of Alzheimer disease (AD) clinical trials is representative of the overall study sample. Methods: Baseline data from 2 ongoing AD clinical trials with 402 and 313 randomized participants were analyzed. Magnetic resonance imaging substudy enrollers (166 participants in trial 1 and 161 participants in trial 2) and nonenrollers were compared on baseline demographic, medical and clinical characteristics separately for the 2 trials. Results: In both trials, enrollers were statistically similar to nonenrollers on most demographic and clinical measures. One study sample showed that enrollers had lower cognitive scores at baseline when compared with nonenrollers: lower Mini Mental State Examination scores (20.15±3.6 vs. 21.04±3.6, P=0.02), and higher Alzheimer's Disease Assessment Scale-cognitive domain scores (24.99±8.5 vs. 23.03±9.3, P=0.03); however, the difference was not considered clinically important and was not observed in the second trial. Conclusions: The groups of individuals who agreed to participate in the imaging substudies of AD trials were remarkably comparable to the comparison groups at baseline on a wide range of demographic and clinical measures; there seems to be a minimal effect of self-selection bias. The Results indicate that it may be reasonable to generalize findings in an imaging substudy to the complete the study population.

Original languageEnglish (US)
Pages (from-to)333-336
Number of pages4
JournalAlzheimer Disease and Associated Disorders
Volume23
Issue number4
DOIs
StatePublished - Oct 2009

Fingerprint

Alzheimer Disease
Demography
Clinical Trials
Population
Selection Bias
Magnetic Resonance Imaging
Alzheimer disease type 2

Keywords

  • AD
  • MRI
  • Randomized clinical trials

ASJC Scopus subject areas

  • Geriatrics and Gerontology
  • Psychiatry and Mental health
  • Gerontology
  • Clinical Psychology

Cite this

MRI substudy participation in alzheimer disease (AD) clinical trials : Baseline comparability of a substudy sample to entire study population. / Raman, Rema; Thomas, Ronald G.; Weiner, Michael W.; Jack, Clifford R Jr.; Ernstrom, Karin; Aisen, Paul S.; Tariot, Pierre N.; Quinn, Joseph F.

In: Alzheimer Disease and Associated Disorders, Vol. 23, No. 4, 10.2009, p. 333-336.

Research output: Contribution to journalArticle

Raman, Rema ; Thomas, Ronald G. ; Weiner, Michael W. ; Jack, Clifford R Jr. ; Ernstrom, Karin ; Aisen, Paul S. ; Tariot, Pierre N. ; Quinn, Joseph F. / MRI substudy participation in alzheimer disease (AD) clinical trials : Baseline comparability of a substudy sample to entire study population. In: Alzheimer Disease and Associated Disorders. 2009 ; Vol. 23, No. 4. pp. 333-336.
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