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Convert between Odds ratios and Risk ratios

Usage

oddsratio_to_riskratio(OR, p0, log = FALSE, ...)

riskratio_to_oddsratio(RR, p0, log = FALSE)

Arguments

OR, RR

Risk ratio of p1/p0 or Odds ratio of odds(p1)/odds(p0), possibly log-ed. OR can also be a logistic regression model.

p0

Baseline risk

log

Take in or output the log of the ratio (such as in logistic models).

...

Arguments passed to and from other methods.

Value

Converted index, or if OR is a logistic regression model, a parameter table with the converted indices.

References

Grant, R. L. (2014). Converting an odds ratio to a range of plausible relative risks for better communication of research findings. Bmj, 348, f7450.

See also

Other convert between effect sizes: d_to_cles(), d_to_r(), eta2_to_f2(), odds_to_probs()

Examples

p0 <- 0.4
p1 <- 0.7

(OR <- probs_to_odds(p1) / probs_to_odds(p0))
#> [1] 3.5
(RR <- p1 / p0)
#> [1] 1.75

riskratio_to_oddsratio(RR, p0 = p0)
#> [1] 3.5
oddsratio_to_riskratio(OR, p0 = p0)
#> [1] 1.75

m <- glm(am ~ factor(cyl), data = mtcars,
         family = binomial())
oddsratio_to_riskratio(m)
#> Warning: 'p0' not provided.RR is relative to the intercept (p0 = 0.73) - make sure your intercept is meaningful.
#> Warning: CIs are back-transformed from the logit scale.
#> Parameter   | Risk Ratio |       95% CI
#> ---------------------------------------
#> (Intercept) |       0.73 |             
#> cyl [6]     |       0.59 | [0.11, 1.16]
#> cyl [8]     |       0.20 | [0.02, 0.70]
#> 
#> Uncertainty intervals (profile-likelihood) and p-values (two-tailed)
#>   computed using a Wald z-distribution approximation.