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49/100

✓ Peer-reviewed alzhub usefulness score 49 out of 100. Risk factors

Topic: Risk, prevention and care in population studies

Several reviews have summarized the prevalence of dementia in mainland China, Hong Kong and Taiwan. However, the influence of methodological factors on the results is seldom considered in these reviews and area prevalence has not been estimated adjusting comprehensively for various research methods between the studies. This study examines area differences across mainland China, Hong Kong and Taiwan with the consideration of methodological factors and the aim of producing estimates of the numbers of people with dementia in these areas. A literature search was conducted in both Chinese and English databases studies to identify the prevalence studies of dementia between 1980 and 2012 in mainland China, Hong Kong and Taiwan. Details of each study, including study designs, screening tools, diagnostic criteria and the results of prevalence, were extracted systematically to examine the effects of methodological factors and area difference by meta-regression. The results of meta-analysis were applied to current population data to provide the best estimated number of people with dementia. 76 studies which were included in the analysis covered 19 provinces, 3 municipalities and 2 nationwide studies in mainland China, 6 studies in Taiwan and 1 study in Hong Kong. After controlling methodological factors (diagnostic criteria, age range, study sample size and sampling method), a pattern of significantly decreasing prevalence was observed from northern, central, southern areas of mainland China, Hong Kong and Taiwan. Based on the DSM-IV diagnostic criteria, the total number of people aged 60 and over with dementia in mainland China, Hong Kong and Taiwan is 8.4 million (4.6%, 95% CI: 3.4, 5.8) and in northern, central and southern areas are 3.8 (5.1%, 95% CI: 4.1, 6.1), 3.2 (4.4%, 95% CI: 3.2, 5.6) and 1.2 (3.9%, 95% CI: 2.3, 5.4) million respectively. This review provided a robust estimate of area difference with the consideration of methodological factors. To understand the factors which cause the geographical variation, a multicentre study with the same design and strict quality control would be needed. Application of the estimated prevalence to national demographics reveals the areas in mainland China which will be facing the greatest challenge.

Key findings

However, the influence of methodological factors on the results is seldom considered in these reviews and area prevalence has not been estimated adjusting comprehensively for various research methods between the studies.
Details of each study, including study designs, screening tools, diagnostic criteria and the results of prevalence, were extracted systematically to examine the effects of methodological factors and area difference by meta-regression.
The results of meta-analysis were applied to current population data to provide the best estimated number of people with dementia. 76 studies which were included in the analysis covered 19 provinces, 3 municipalities and 2 nationwide studies in mainland China, 6 studies in Taiwan and 1 study in Hong Kong.
After controlling methodological factors (diagnostic criteria, age range, study sample size and sampling method), a pattern of significantly decreasing prevalence was observed from northern, central, southern areas of mainland China, Hong Kong and Taiwan.

Why it matters

This review combined 76 studies to estimate dementia prevalence in mainland China, Hong Kong, and Taiwan while accounting for differences in research methods. It provides area estimates of how many people have dementia but does not test any treatment, cure, or prevention.

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Study details

Study designmeta-analysis
Effect size4.6%; 5.1%; 4.4%
Evidence strengthHigh

How this study scored 49/100

Published in a peer-reviewed journal, and it is a meta-analysis pooling many studies. Scored zero for sample size and studied in people because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Alzheimer s & Dementia)
Journal's citation record	2 / 4	Alzheimer s & Dementia: journal h-index 228 (OpenAlex, 2026-10-29)
Study design	12 / 12	A meta-analysis pooling many studies
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	2013 — within 20 year(s) of the newest study here
Sample size	0 / 4	Participant count not stated — scores zero (not stated in the record — scored 0)
Effect reported	2 / 3	Effect reported as a number, without an interval or test
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	A review of other studies — randomisation is not credited here
Times cited	1 / 7	Cited 1 times (OpenAlex, 2026-10-10)
Citations per year	0 / 5	0.1 citations a year over 15 year(s) since 2013
Impact for its field and year	0 / 6	Cited 0.0× 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	4 / 4	Last-listed author Carol Brayne: h-index 159 (OpenAlex, whole career)
Institution's track record	2 / 3	Johns Hopkins University: institution h-index 2,306 (OpenAlex)
Multi-centre collaboration	2 / 3	OpenAlex lists 5 institution(s) in 3 countries
Indexed in PubMed	1 / 2	Not in PubMed, but has a DOI
Free to read	0 / 2	Behind a paywall — scores zero
Total	49 / 100	—

What each of these 20 components measures, and what this score is not →

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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. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.

APA 7th

Wu, Y., Lee, H., Norton, S., Chen, C., Chen, H., He, C., et al. (2013). O4–04–02: Prevalence studies of dementia in mainland China, Hong Kong and Taiwan: A systematic review and meta‐analysis. Alzheimer s & Dementia. https://doi.org/10.1016/j.jalz.2013.04.353

Vancouver

Wu Y, Lee H, Norton S, Chen C, Chen H, He C, et al. O4–04–02: Prevalence studies of dementia in mainland China, Hong Kong and Taiwan: A systematic review and meta‐analysis. Alzheimer s & Dementia. 2013. doi:10.1016/j.jalz.2013.04.353.

BibTeX

@article{wu2013-0a28185d,
  author  = {Wu, Yu‐Tzu and Lee, Hsin‐Yi and Norton, Sam and Chen, Chuanfeng and Chen, Hongxia and He, Chenglin and Fleming, Jane and Matthews, Fiona E. and others},
  title   = {{O4–04–02: Prevalence studies of dementia in mainland China, Hong Kong and Taiwan: A systematic review and meta‐analysis}},
  journal = {Alzheimer s \& Dementia},
  year    = {2013},
  doi     = {10.1016/j.jalz.2013.04.353},
  url     = {https://doi.org/10.1016/j.jalz.2013.04.353}
}

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