Branching logic from the REDCap Data Dictionary is parsed into R Code and returned as expressions. These can be evaluated if desired and allow the user to determine if missing values are truly missing or not required because the branching logic prevented the variable from being presented.
parseBranchingLogic(l)
Returns a list of unevaluated expressions.
A vector of REDCap branching logic statements. These are usually
passed as the vector meta_data$branching_logic
.
Benjamin Nutter
For a study, I was asked to identify which subjects had missing
values so that remaining data could be collected. The initial pass of
is.na
produced a lot of subjects missing values where there was no
need to collect data because they did not qualify for some variables in
the branching logic. Parsing the logic allowed me to determine which
values we expected to be missing and narrow the search to just those
subjects with legitimately missing values.
The utility of this function is limited to simple logic where all of the data exist within the same row. Any complex statements using events will result in a failure.