fisher {twoxtwo}

Fisher's exact test

Description

This function conducts a Fisher's exact test using specified exposure and outcome. Internally the function uses fisher.test to test independence of twoxtwo rows and columns. The output of the function includes the odds ratio, the lower/upper bounds for the confidence interval around the estimate, and the p-value from the test.

Usage

fisher(
  .data,
  exposure,
  outcome,
  alternative = "two.sided",
  conf_level = 0.95,
  or = 1,
  ...
)

Arguments

.data

Either a data frame with observation-level exposure and outcome data or a twoxtwo object

exposure

Name of exposure variable; ignored if input to .data is a twoxtwo object

outcome

Name of outcome variable; ignored if input to .data is a twoxtwo object

alternative

Alternative hypothesis for test; must be one of "two.sided", "greater", or "less"; default is "two.sided"

conf_level

Confidence level for the confidence interval; default is 0.95

or

Hypothesized odds ratio; default is 1

...

Additional arguments passed to twoxtwo function; ignored if input to .data is a twoxtwo object

Value

A tibble with the following columns:

• test: Name of the test conducted

• estimate: Point estimate from the test

• ci_lower: The lower bound of the confidence interval for the estimate

• ci_upper: The upper bound of the confidence interval for the estimate

• statistic: Test statistic from the test (NA for fisher())

• df: Degrees of freedom parameter for the test statistic (NA for fisher())

• pvalue: P-value from the test

• exposure: Name of the exposure variable followed by +/- levels (e.g. smoking::yes/no)

• outcome: Name of the outcome variable followed by +/- levels (e.g. heart_disease::yes/no)