tipr (version 0.4.0)

tip_or: Tip an observed odds ratio with a normally distributed confounder.

Description

choose one of the following, and the other will be estimated:

• smd

• outcome_association

Usage

tip_or(
  effect,
  smd = NULL,
  outcome_association = NULL,
  verbose = TRUE,
  or_correction = FALSE
)

Arguments

effect

Numeric positive value. Observed exposure - outcome odds ratio. This can be the point estimate, lower confidence bound, or upper confidence bound.

smd

Numeric. Estimated difference in scaled means between the unmeasured confounder in the exposed population and unexposed population

outcome_association

Numeric positive value. Estimated association between the unmeasured confounder and the outcome

verbose

Logical. Indicates whether to print informative message. Default: TRUE

or_correction

Logical. Indicates whether to use a correction factor. The methods used for this function are based on relative risks. For rare outcomes, an odds ratio approximates a relative risk. For common outcomes, a correction factor is needed. If you have a common outcome (>15%), set this to TRUE. Default: FALSE.

Value

Data frame.

Examples

# NOT RUN {
## to estimate the association between an unmeasured confounder and outcome
## needed to tip analysis
tip_or(1.2, smd = -2)

## to estimate the number of unmeasured confounders specified needed to tip
## the analysis
tip_or(1.2, smd = -2, outcome_association = .99)

## Example with broom
if (requireNamespace("broom", quietly = TRUE) &&
    requireNamespace("dplyr", quietly = TRUE)) {
  glm(am ~ mpg, data = mtcars, family = "binomial") %>%
   broom::tidy(conf.int = TRUE, exponentiate = TRUE) %>%
   dplyr::filter(term == "mpg") %>%
   dplyr::pull(conf.low) %>%
   tip_or(outcome_association = 2.5, or_correction = TRUE)
}
# }