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Prevalence ratio estimation via logistic regression: a tool in R
Leila D Amorim1, Raydonal Ospina2
1Departamento de Estatística, Universidade Federal da Bahia, Instituto de Matemática e Estatística, Av. Ademar de Barros, s/n, Campus de Ondina, 40170-110 Salvador, BA, Brazil.
Odds ratios (OR) are often misinterpreted as prevalence ratios (PR) in cross-sectional studies. The new prLogistic R package helps accurately estimate prevalence ratios using logistic regression for both independent and correlated data.
Area of Science:
- Biostatistics
- Epidemiology
- Statistical Software
Background:
- Odds ratios (OR) are frequently misinterpreted as prevalence ratios (PR) in cross-sectional studies, an equivalence that holds only under specific conditions.
- Logistic regression is a common statistical tool for binary outcomes, often yielding adjusted ORs.
- Accurate estimation of prevalence ratios is crucial for understanding disease distribution and risk factors.
Purpose of the Study:
- To introduce the prLogistic R package for estimating prevalence ratios (PR) from logistic regression models.
- To provide a tool that addresses the misinterpretation of odds ratios (OR) as PRs in cross-sectional studies.
- To facilitate the analysis of both independent and correlated binary data for PR estimation.
Main Methods:
- Development of the prLogistic package for the R statistical computing environment.
- Utilizing logistic regression models adjusted by the delta method and bootstrap techniques.
- Application to independent observations and clustered/correlated binary data.
Main Results:
- The prLogistic package enables the estimation of adjusted prevalence ratios (PR) using logistic regression.
- The package provides methods for handling both independent and correlated binary data.
- Illustrative applications demonstrate the practical utility of the package in real-world scenarios.
Conclusions:
- The prLogistic R package offers a valuable tool for biostatisticians and epidemiologists.
- It aids in the accurate estimation of prevalence ratios, avoiding common misinterpretations of odds ratios.
- The package supports the analysis of complex data structures, including clustered observations.
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