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This page is alzhub.org's plain-English summary of a published study, not the paper itself. It is generated from the record we hold for this study, sourced and linked below — check the original for the full text and methods.

✓ Peer-reviewed alzhub usefulness score 53 out of 100. How common it is

Topic: Risk, prevention and care in population studies

Objective To empirically compare the Cox, log-binomial, Poisson and logistic regressions to obtain estimates of prevalence ratios (PR) in cross-sectional studies. Methods Data from a population-based cross-sectional epidemiological study (n = 2072) on elderly people in Sao Paulo (Southeastern Brazil), conducted between May 2003 and April 2005, were used. Diagnoses of dementia, possible cases of common mental disorders and self-rated poor health were chosen as outcomes with low, intermediate and high prevalence, respectively. Confounding variables with two or more categories or continuous values were used. Reference values for point and interval estimates of prevalence ratio (PR) were obtained by means of the Mantel-Haenszel stratification method. Adjusted PR estimates were calculated using Cox and Poisson regressions with robust variance, and using log-binomial regression. Crude and adjusted odds ratios (ORs) were obtained using logistic regression. Results The point and interval estimates obtained using Cox and Poisson regressions were very similar to those obtained using Mantel-Haenszel stratification, independent of the outcome prevalence and the covariates in the model. The log-binomial model presented convergence difficulties when the outcome had high prevalence and there was a continuous covariate in the model. Logistic regression produced point and interval estimates that were higher than those obtained using the other methods, particularly when for outcomes with high initial prevalence. If interpreted as PR estimates, the ORs would overestimate the associations for outcomes with low, intermediate and high prevalence by 13%, almost by 100% and fourfold, respectively. Conclusions In analyses of data from cross-sectional studies, the Cox and Poisson models with robust variance are better alternatives than logistic regression is. The log-binomial regression model produces unbiased PR estimates, but may present convergence difficulties when the outcome is very prevalent and the confounding variable is continuous.

Key findings

Why it matters

This methods study compared statistical approaches for estimating prevalence ratios in cross-sectional studies, using dementia as one outcome. It found that Cox and Poisson regressions produced estimates very similar to Mantel-Haenszel stratification, while logistic regression produced different estimates.

Study details

How this study scored 53/100
How this study's score is builtJournal tier 7 of 10; Journal's citation record 1 of 4; Study design 4 of 12; Strength of evidence 1 of 5; Peer-review validation 10 of 10; How recent 1 of 5; Sample size 3 of 4; Effect reported 0 of 3; Studied in people 3 of 3; Randomised / blinded 0 of 2; Times cited 6 of 7; Citations per year 4 of 5; Impact for its field and year 4 of 6; Cited by studies here 0 of 6; Still being cited 3 of 4; Senior author's track record 3 of 4; Institution's track record 1 of 3; Multi-centre collaboration 0 of 3; Indexed in PubMed 2 of 2; Free to read 0 of 2. Total 53 of 100.53 of 100 points earned47 not earned

Published in a peer-reviewed journal, and it is a snapshot of people at one point in time. Scored zero for effect reported and randomised / blinded because the record does not state it.

ComponentPointsWhy
Journal tier 7 / 10 Tier 3 — peer-reviewed journal (Revista de saude publica)
Journal's citation record 1 / 4 Revista de Saúde Pública: journal h-index 142 (OpenAlex, 2026-10-29)
Study design 4 / 12 A snapshot of people at one point in time
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 2008 — within 20 year(s) of the newest study here
Sample size 3 / 4 2,072 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)
Randomised / blinded 0 / 2 No randomisation or blinding stated — scores zero (not stated in the record — scored 0)
Times cited 6 / 7 Cited 583 times (OpenAlex, 2026-10-10)
Citations per year 4 / 5 29.1 citations a year over 20 year(s) since 2008
Impact for its field and year 4 / 6 Cited 8.7× 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 3 / 4 Cited 90 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record 3 / 4 Last-listed author Paulo Rossi Menezes: h-index 65 (OpenAlex, whole career)
Institution's track record 1 / 3 Universidade de São Paulo: institution h-index 936 (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 19009156)
Free to read 0 / 2 Behind a paywall — scores zero
Total 53 / 100 —

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

Read the original

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

Coutinho, L. M., Scazufca, M., & Menezes, P. R. (2008). Methods for estimating prevalence ratios in cross-sectional studies. Revista de saude publica. https://doi.org/10.1590/s0034-89102008000600003

Vancouver

Coutinho LM, Scazufca M, Menezes PR. Methods for estimating prevalence ratios in cross-sectional studies. Revista de saude publica. 2008. doi:10.1590/s0034-89102008000600003. PMID: 19009156.

BibTeX

@article{coutinho2008-19009156,
  author  = {Coutinho, L. M. and Scazufca, M. and Menezes, P. R.},
  title   = {{Methods for estimating prevalence ratios in cross-sectional studies}},
  journal = {Revista de saude publica},
  year    = {2008},
  doi     = {10.1590/s0034-89102008000600003},
  pmid    = {19009156},
  url     = {https://doi.org/10.1590/s0034-89102008000600003}
}

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