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44/100

✓ Peer-reviewed alzhub usefulness score 44 out of 100. Treatments

Topic: Amyloid, tau and blood-test diagnosis

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.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

Raman, R., Thomas, R. G., Weiner, M. W., Jack, C. R., Ernstrom, K., Aisen, P. S., et al. (2009). MRI substudy participation in Alzheimer disease (AD) clinical trials: baseline comparability of a substudy sample to entire study population. Alzheimer disease and associated disorders. https://doi.org/10.1097/wad.0b013e3181aba588

Vancouver

Raman R, Thomas RG, Weiner MW, Jack CR, Ernstrom K, Aisen PS, et al. MRI substudy participation in Alzheimer disease (AD) clinical trials: baseline comparability of a substudy sample to entire study population. Alzheimer disease and associated disorders. 2009. doi:10.1097/wad.0b013e3181aba588. PMID: 19571733.

BibTeX

@article{raman2009-19571733,
  author  = {Raman, R. and Thomas, R. G. and Weiner, M. W. and Jack, C. R. and Ernstrom, K. and Aisen, P. S. and Tariot, P. N. and Quinn, J. F.},
  title   = {{MRI substudy participation in Alzheimer disease (AD) clinical trials: baseline comparability of a substudy sample to entire study population}},
  journal = {Alzheimer disease and associated disorders},
  year    = {2009},
  doi     = {10.1097/wad.0b013e3181aba588},
  pmid    = {19571733},
  url     = {https://doi.org/10.1097/wad.0b013e3181aba588}
}

Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record names 8 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.

Key findings

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.
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.
The results indicate that it may be reasonable to generalize findings in an imaging substudy to the complete the study population.

Why it matters

This study compared participants who enrolled in MRI substudies of Alzheimer's trials with those who did not, and found they were largely similar at baseline. It addresses whether imaging substudy samples are representative, not whether any treatment works.

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Study details

Participants166
Evidence strengthHigh

How this study scored 44/100

Published in a peer-reviewed journal. Scored zero for study design and effect reported because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Alzheimer disease and associated disorders)
Journal's citation record	1 / 4	Alzheimer Disease & Associated Disorders: journal h-index 131 (OpenAlex, 2026-10-29)
Study design	0 / 12	No study design recorded — scores zero, not guessed (not stated in the record — scored 0)
Strength of evidence	5 / 5	Rated “high” in our summary
Peer-review validation	10 / 10	Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent	1 / 5	2009 — within 20 year(s) of the newest study here
Sample size	2 / 4	166 participants
Effect reported	0 / 3	No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people	3 / 3	Studied in people (participant count stated)
Randomized / blinded	1 / 2	Randomized (as stated in the record)
Times cited	2 / 7	Cited 5 times (OpenAlex, 2026-10-10)
Citations per year	0 / 5	0.3 citations a year over 19 year(s) since 2009
Impact for its field and year	1 / 6	Cited 0.4× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here	1 / 6	Cited by 1 other studies in this library
Still being cited	0 / 4	Cited 0 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	4 / 4	Last-listed author Joseph F. Quinn: h-index 109 (OpenAlex, whole career)
Institution's track record	2 / 3	University of California, San Francisco: institution h-index 1,915 (OpenAlex)
Multicenter collaboration	2 / 3	OpenAlex lists 6 institution(s) in 1 country
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 19571733)
Free to read	0 / 2	Behind a paywall — scores zero
Total	44 / 100	—

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