NaVar: Create new variable(s) indicating if there are missing values...
In DataCombine: Tools for Easily Combining and Cleaning Data Sets

Create new variable(s) indicating if there are missing values in other variable(s)

1	NaVar(data, Var, Stub = "Miss_", reverse = FALSE, message = TRUE)

`data`	a data frame object.
`Var`	a character vector naming the variable(s) within which you would like to identify missing values.
`Stub`	a character string indicating the stub you would like to append to the new variables' name(s).
`reverse`	logical. If `reverse = FALSE` then missing values are coded as `1` and non-missing values are coded as `0`. If `reverse = TRUE` then missing values are coded as `0` and non-missing values are coded as `1`.
`message`	logical. Whether or not to give you a message about the names of the new variables that are created.

# Create data frame
a <- c(1, 2, 3, 4, NA)
b <- c( 1, NA, 3, 4, 5)
ABData <- data.frame(a, b)

# Create varibles indicating missing values in columns a and b
ABData1 <- NaVar(ABData, Var = c('a', 'b'))

# Create varible indicating missing values in columns a with reversed dummy
ABData2 <- NaVar(ABData, Var = 'a', reverse = TRUE, message = FALSE)