R for CDISC submissions has been promoted for several years now. More importantly, it is no longer just a slogan—many organizations have actually started using it in real projects, particularly for CDISC datasets and TFLs.
That raises an important question: What have we learned so far, and is it time to reconsider some of the original arguments for adopting R?
This discussion is limited to R for CDISC datasets and TFLs, not R used for specialized calculations by biostatisticians.
One of the early arguments was:
Students cannot learn SAS sufficiently at university, but they are already familiar with R.
That may be partly true, but being familiar with base R is very different from being familiar with clinical programming packages, CDISC implementation, controlled terminology, traceability, and submission requirements. Students may know R syntax, but they still need to learn the clinical programming ecosystem—and many of those packages are relatively new, constantly evolving, and not necessarily intuitive.
Another argument was:
R is cheaper.
But is it really cheaper for submissions?
Validation, reproducibility, environment management, package qualification, version control, auditability, and regulatory documentation can require substantial effort. Some of the work that was traditionally handled within established SAS programming processes may now shift to programming teams and IT. The cost may not disappear; it may simply move to different parts of the organization.
A third argument was:
R benefits from strong open-source community support.
That is certainly true. The R community is active and innovative. However, the rapid pace of package development also creates challenges. Functions may be deprecated, behavior may change, dependencies may break, and code that worked two years ago may no longer work without modification. I understand `renv` can lock the enviroment for the project, but does it also means Stat_programmer must pay more attention on package learning?
R clearly has meaningful applications in clinical research, especially for exploratory analyses, visualization, interactive reporting, and statistical methodology. However, many of these advantages seem particularly relevant to biostatisticians rather than necessarily to standardized CDISC submission production.
Compared with SAS, R is often more flexible. But flexibility can also increase the coding workload. Statistical programmers may need to spend more time managing code, package versions, validation frameworks, and technical infrastructure—rather than focusing on the scientific or regulatory objectives of the project.