epitools (version 0.5-9)

epitable: Create r x c contigency table (exposure levels vs. binary outcome)

Description

Create r x c contigency table for r exposure levels and c outcome levels

Usage

epitable(..., ncol =2, byrow = TRUE,
         rev = c("neither", "rows", "columns", "both"))

Arguments

...

see details

ncol

number of columns = 2 (default) when a table is constructed from a vector or sequence of numbers

byrow

Default is TRUE and single vector or collection of numbers is read in row-wise. Set to FALSE to read in column-wise.

rev

reverse order of "rows", "colums", "both", or "neither" (default)

Value

Returns r x 2 contingency table, usually for additional analyses.

Details

Creates r x 2 table with r exposure levels and 2 outcome levels (No vs. Yes). Arguments can be one of the following: (1) four or more integers that be converted into r x 2 table (the number of integers must be even), (2) two categorical vectors (1st vector is exposure with r levels, 2nd vector is outcome with 2 levels), (3) r x 2 contingency table, or (4) single vector that be converted into r x 2 table (the number of integers must be even). The contingency table created by this function is usually used for additional analyses, for example, the epitab function.

References

none

See Also

epitable

Examples

## single vector
dat <- c(88, 20, 555, 347)
epitable(dat)

## 4 or more integers
epitable(1,2,3,4,5,6)

## single matrix
epitable(matrix(1:6, 3, 2))

## two categorical vectors
exposure <- factor(sample(c("Low", "Med", "High"), 100, rep=TRUE),
                   levels=c("Low", "Med", "High"))
outcome <- factor(sample(c("No", "Yes"), 100, rep=TRUE))
epitable(exposure, outcome)
epitable("Exposure"=exposure, "Disease"=outcome)

## reversing row and/or column order
zz <- epitable("Exposure Level"=exposure, "Disease"=outcome)
zz
epitable(zz, rev = "r")
epitable(zz, rev = "c")
epitable(zz, rev = "b")