Likelihood Ratio Test and the Evidential Approach for 2 × 2 Tables
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View abstract on PubMed
Summary
This summary is machine-generated.The likelihood ratio test (LRT) is recommended over the chi-squared (χ2) test for analyzing 2 × 2 contingency tables when testing binomial proportions. The χ2 test is better suited for assessing data integrity and low variance scenarios.
Area Of Science
- Statistics
- Biostatistics
- Medical Research
Background
- Categorical data analysis using 2 × 2 contingency tables is prevalent in medical research.
- Commonly used statistics include risk difference, risk ratio, odds ratio, and log odds.
- Both chi-squared (χ2) tests and likelihood ratio tests (LRT) are employed for analysis.
Purpose Of The Study
- To determine the appropriate statistical test for analyzing 2 × 2 contingency tables.
- To evaluate the suitability of the χ2 test versus the LRT for specific research questions.
- To advocate for the use of the LRT for testing binomial proportions and an evidential approach for data integrity.
Main Methods
- Literature review.
- Examination of theoretical foundations.
- Analysis of simulation and empirical data.
Main Results
- The likelihood ratio test (LRT) is the preferred method for testing the equality of binomial proportions.
- The chi-squared (χ2) test is often misused for this purpose.
- The χ2 test is appropriate for scenarios where low variance or data integrity is of interest.
Conclusions
- The LRT provides a more consistent and coherent approach for testing binomial proportions.
- An evidential approach using log likelihood ratios is recommended for flexibility in testing proportions or variance.
- Findings are applicable to larger and multi-way contingency tables.
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