Detects whether path is a directory of XPT datasets (a real study) or a
CORE test-case data/ directory (_variables.csv + one CSV per dataset,
usually also .env and _datasets.csv), and reads either into the same
internal representation, so the evaluator never has to know which one it
got.
Value
A study object: list(datasets = <named list of domain -> list(data, meta, label)>, define, ct = NULL, standard = list(product, version)). define is the parsed Define-XML if one was
found in path and the xml2 package is installed, and NULL
otherwise; ct is always NULL (controlled terminology is not
bundled). Each data is a data.table::data.table();
each meta is a data.table with columns variable, label, type;
label is the dataset's own label (e.g. "Adverse Events"), or NA if
unavailable. standard is the study's declared standard/version (e.g.
list(product = "SDTMIG", version = "3-4")), read from a CORE test
case's .env file - both NA for a real XPT-based study (no .env).
Details
Character columns use "" for blank/missing (never NA) to match how
SAS XPT round-trips blanks; numeric columns use NA. Column types are
taken from the source (XPT's own types, or _variables.csv's declared
Char/Num) rather than guessed from the data, so numeric-looking
identifiers (e.g. "007") are never silently coerced.
Examples
dir <- tempfile("coreval_study_")
dir.create(dir)
haven::write_xpt(data.frame(USUBJID = c("1", "2"), AGE = c(30, 65)), file.path(dir, "dm.xpt"))
study <- read_study(dir)
study$datasets$DM$data
#> USUBJID AGE
#> <char> <num>
#> 1: 1 30
#> 2: 2 65
unlink(dir, recursive = TRUE)