lab_change: Determine if a lab changed by a set amount within a specific...
In bgulbis/edwr: Standardized Functions for Working with Data from the EDW

Description Usage Arguments Details Value Examples

lab_change checks for changes in lab values

1	lab_change(x, .lab, change.by, FUN, back = 2)

`x`	A data frame with lab data
`.lab`	A character string indicating the name of the lab to evaluate
`change.by`	A numeric indicating the threshold for lab changes
`FUN`	A function for `rollapplyr`, most commonly max or min
`back`	An optional numeric specifying the number of days back to go. Defaults to 2 days.

This function takes a data frame with lab data for a single lab and checks whether the lab changes by a certain amount within a given period of time.

For FUN, use max when looking for a decrease in lab value, and min when looking for an increase in lab value.

A data frame

# checks for a >= 2 decrease in the hemoglobin value within the past 2 days
x <- tidy_data(labs)

print(head(
  lab_change(x, "hgb", -2, max, back = 2)
))