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Slowing the progression of Alzheimer disease: methodologic issues
Leber P.. Alzheimer disease and associated disorders, 1997-01-01
Topic: Amyloid, tau and blood-test diagnosis
The evidence to support a claim that a new drug will slow the progression of Alzheimer disease (AD) must derive from epistemologically valid research methods. Although agency regulations do not specify the magnitude of an effect that a drug must possess to be granted a claim as a treatment for AD, the evidence to support any claim must be adduced in adequate and well-controlled clinical investigations and must meet the standard of "substantial evidence." Because a claim presented in drug product labeling may not be false or misleading in any particular, a distinction must be made between treatments that provide a "symptomatic" benefit and those that alter the course of dementia. Examples of some of the difficulties likely to be encountered by sponsors seeking to develop evidence to support a claim that a new drug slows the progression of dementia are presented. A suggestion is made for a clinical trial design, designated as the "randomized start design," that may be useful in such a question. Why this design might overcome many of the difficulties, both practical and ethical, present in the "discontinuation" design, the design ordinarily proposed to assess a drug's effect on disease progression, is discussed.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
APA 7th
Leber, P. (1997). Slowing the progression of Alzheimer disease: methodologic issues. Alzheimer disease and associated disorders.
Vancouver
Leber P. Slowing the progression of Alzheimer disease: methodologic issues. Alzheimer disease and associated disorders. 1997. PMID: 9348423.
BibTeX
@article{leber1997-9348423,
author = {Leber, P.},
title = {{Slowing the progression of Alzheimer disease: methodologic issues}},
journal = {Alzheimer disease and associated disorders},
year = {1997},
pmid = {9348423}
}
Built from the record alzhub holds for this paper, not looked up. This record has no DOI, so the citation leaves it out. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
Key findings
- The evidence to support a claim that a new drug will slow the progression of Alzheimer disease (AD) must derive from epistemologically valid research methods.
- Although agency regulations do not specify the magnitude of an effect that a drug must possess to be granted a claim as a treatment for AD, the evidence to support any claim must be adduced in adequate and well-controlled clinical investigations and must meet the standard of "substantial evidence." Because a claim presented in drug product labeling may not be false or misleading in any particular, a distinction must be made between treatments that provide a "symptomatic" benefit and those that alter the course of dementia.
- Examples of some of the difficulties likely to be encountered by sponsors seeking to develop evidence to support a claim that a new drug slows the progression of dementia are presented.
- A suggestion is made for a clinical trial design, designated as the "randomized start design," that may be useful in such a question.
- Why this design might overcome many of the difficulties, both practical and ethical, present in the "discontinuation" design, the design ordinarily proposed to assess a drug's effect on disease progression, is discussed.
Why it matters
This is a methods paper about how to design and evaluate trials that claim to slow Alzheimer's disease progression. It does not test any treatment and provides no evidence for curing or preventing the disease.
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Study details
- Evidence strengthHigh
How this study scored 34/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on journal's citation record, so that was left out: it earned 33 of the 96 points we could judge it on, which is 34 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Alzheimer disease and associated disorders) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| 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 | 1997 — older than 20 years, still counted |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 4 / 7 | Cited 98 times (OpenAlex, 2026-10-10) |
| Citations per year | 2 / 5 | 3.2 citations a year over 31 year(s) since 1997 |
| Impact for its field and year | 1 / 6 | Cited 0.8× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 0 / 4 | Cited 0 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 1 / 4 | Last-listed author Paul D. Leber: h-index 14 (OpenAlex, whole career) |
| Institution's track record | 0 / 3 | United States Food and Drug Administration: institution h-index 651 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 9348423) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 33 / 96 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 33 of the 96 points we could judge it on is 34 out of 100. |
| Total | 34 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
May need a subscription Unpaywall, Europe PMC and OpenAlex found no free copy of the full text (checked 10 Oct 2026), so the publisher may charge for it. The PubMed abstract is free.
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