What problem does it solve? Mapping raw EDC/eCRF clinical data to CDISC SDTM domains requires choosing the correct derivation algorithm per variable, applying controlled terminology recoding, and producing ISO 8601 dates — mistakes like wrong codelists or manual date parsing silently corrupt submission data. This Skill produces executable, traceable R code following the sdtm.oak algorithm framework with built-in QC review annotations. ## Core Features & Use Cases - Algorithm selection guidance: Chooses among assign_no_ct(), assign_ct(), hardcode_ct(), hardcode_no_ct(), assign_datetime(), and condition_add() based on whether each variable has controlled terminology and whether values come from raw data or are hardcoded. - Full domain workflow: Covers Events (AE, CM, MH), Interventions (EX), Findings (VS, LB, EG with per-test stacking), and SUPP-- supplemental domains, including sequence numbers, study day derivation, and baseline flags. - QC traceability: Places # REVIEW: annotations at every protocol-specific decision point (date formats, codelist selection, baseline visit definitions) and enforces an output checklist with required-variable and duplicate-SEQ checks. - Use Case: Given a raw adverse events dataset and a CT specification CSV, generate a complete AE domain derivation script with AETERM, AESEV, AESTDTC, AESEQ, and AESTDY, ready for QC review. ## Quick Start Ask the assistant to derive an SDTM AE domain from your raw adverse events dataset using sdtm.oak, providing the raw data and controlled terminology specification.