Implementation of Clinical Data Interchange Standard Consortium (CDISC) standards to Real-World Data: Challenges and Strategies in SDTM Development in the Setting of Observational Studies

Introduction. In the realm of clinical trials, the Clinical Data Interchange Standard Consortium (CDISC) standards have become increasingly mandated by numerous national and regional regulatory agencies. For several years, the modeling of observational studies (OSs) was not explicitly addressed in the SDTM Implementation Guide (IG). However, in 2024, the document “Considerations for SDTM Implementation in Observational Studies and Real-World Data v1.0 (Final)” was released. Aim. This paper aims to describe the challenges encountered when applying the CDISC SDTM standard to map data from real-world studies before the release of the CDISC document dedicated to OSs. Methods. The SDTM mapping process began exploring the rationale for using SDTM datasets and continued through programming, and validation. Results. Data from three OSs conducted by IQVIA Solutions Italy between 2020 and 2024 and enrolling 1543 patients affected by asthma, diabetes and a rare disease were analyzed. A total of 86 SDTM domains were created, 95% of which were conventional SDTM domains according to the CDISC guidelines. Main validation issues arose because Exposure dataset was missing, or because variable EPOCH was not found or due to violation of conformance rules (e.g. “Value not found in codelist”), as these rules, designed for clinical trials had not been adapted yet to OSs. These issues were managed on a case-by-case basis through changes to the SDTM domains or by providing documented justification. Conclusions. The challenges experienced till 2024 can now be solved thanks to the document released for OSs. However, implementing SDTM for OSs still needs ad-hoc solutions.