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Table 4 Comparison of log-binomial and Robust Poisson methods for analysis of no pain associated with covariates*

From: A comparison of two methods for estimating prevalence ratios

Independent Variable Level Log Prevalence Ratio Estimate (SE) P-Value
   Log-Binomial Robust Poisson Log-Binomial Robust Poisson
Analgesic A
B
1.0228 (0.3951)
1.0979 (0.3898)
1.0628 (0.3902)
1.1515 (0.3882)
0.0002 0.0123
Gender Female 0.2259 (0.0726) 0.4584 (0.1808) 0.0416 0.0112
Age   -0.0376 (0.0119) -0.0635 (0.0183) 0.0075 0.0005
  1. * Wald tests were used for the Robust Poisson method, and likelihood ratio tests were used for the log-binomial method. The latter were obtained by fitting a model without the effect being tested. The log-binomial method failed to converge for the 2 models containing both analgesic and age, and the COPY method approximation was used.
  2. The intercept estimate was 1.1200 for the log-binomial method and 2.7438 for the Robust Poisson method. Of the 60 probability estimates, 9 were greater than unity for the Robust Poisson method, and the largest was 1.30.