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Mild cognitive impairment as a diagnostic entity
Petersen RC.. Journal of internal medicine, 2004-09-01
Topic: Risk, prevention and care in population studies
The concept of cognitive impairment intervening between normal ageing and very early dementia has been in the literature for many years. Recently, the construct of mild cognitive impairment (MCI) has been proposed to designate an early, but abnormal, state of cognitive impairment. MCI has generated a great deal of research from both clinical and research perspectives. Numerous epidemiological studies have documented the accelerated rate of progression to dementia and Alzheimer's disease (AD) in MCI subjects and certain predictor variables appear valid. However, there has been controversy regarding the precise definition of the concept and its implementation in various clinical settings. Clinical subtypes of MCI have been proposed to broaden the concept and include prodromal forms of a variety of dementias. It is suggested that the diagnosis of MCI can be made in a fashion similar to the clinical diagnoses of dementia and AD. An algorithm is presented to assist the clinician in identifying subjects and subclassifying them into the various types of MCI. By refining the criteria for MCI, clinical trials can be designed with appropriate inclusion and exclusion restrictions to allow for the investigation of therapeutics tailored for specific targets and populations.
Key findings
- It is suggested that the diagnosis of MCI can be made in a fashion similar to the clinical diagnoses of dementia and AD.
Why it matters
This 2004 review describes mild cognitive impairment (MCI) as "an early, but abnormal, state of cognitive impairment" between normal ageing and very early dementia, and argues it can be diagnosed "in a fashion similar to the clinical diagnoses of dementia and AD", presenting an algorithm to identify people with MCI and sort them into subtypes. It notes that studies have documented an "accelerated rate of progression" to dementia and Alzheimer's in people with MCI, but also that the precise definition has been controversial. It proposes criteria rather than testing them on patients, and it reports no treatment.
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Study details
- Evidence strengthLow
How this study scored 57/100
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.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Journal of internal medicine) |
| Journal's citation record | 2 / 4 | Journal of Internal Medicine: journal h-index 237 (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 | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2004 — 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 | 7 / 7 | Cited 7,858 times (OpenAlex, 2026-10-10) |
| Citations per year | 5 / 5 | 327.4 citations a year over 24 year(s) since 2004 |
| Impact for its field and year | 6 / 6 | Cited 60.1× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 6 / 6 | Cited by 446 other studies in this library |
| Still being cited | 4 / 4 | Cited 1,291 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Ronald Carl Petersen: h-index 209 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Mayo Clinic: institution h-index 1,606 (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 15324362) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 57 / 100 | — |
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Read the original
- DOI: 10.1111/j.1365-2796.2004.01388.x
- PubMed: 15324362
- Original source →
- Free full text: Journal of Internal Medicine →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Petersen, R. C. (2004). Mild cognitive impairment as a diagnostic entity. Journal of internal medicine. https://doi.org/10.1111/j.1365-2796.2004.01388.x
Vancouver
Petersen RC. Mild cognitive impairment as a diagnostic entity. Journal of internal medicine. 2004. doi:10.1111/j.1365-2796.2004.01388.x. PMID: 15324362.
BibTeX
@article{petersen2004-15324362,
author = {Petersen, R. C.},
title = {{Mild cognitive impairment as a diagnostic entity}},
journal = {Journal of internal medicine},
year = {2004},
doi = {10.1111/j.1365-2796.2004.01388.x},
pmid = {15324362},
url = {https://doi.org/10.1111/j.1365-2796.2004.01388.x}
}
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