Study Build and Database Design
What you must know
Study build translates the protocol into a database. The annotated CRF (aCRF) maps each collected field to a dataset and variable. CDISC SDTM defines submission structure; CDASH defines collection. Understand that collection should align with CDASH where possible to ease later SDTM mapping. Know the role of the data management plan (DMP), CRF design principles, and the edit check specification.
Concepts to master
Know the difference between a form, a visit, and a schedule of assessments. Understand controlled terminology, code lists, and the importance of not collecting data that will never be analyzed. Recognize that database design must support query logic, derivations, and external data merges. Know that the build must be tested (UAT) before go-live.
Traps
Questions often confuse SDTM (submission) with CDASH (collection). Watch for designs that collect free text where a coded field is required, or that embed derivations in the entry form rather than the transformation layer. Another trap: assuming the aCRF is optional when it is essential for traceability.
Rule of thumb
Collect once, use many times: design fields so the same data supports EDC entry, SDTM mapping, and analysis without re-entry. If a field has no downstream use, question why it is collected.