SDTM v2.0 is the first major release since the model's original publication in 2004. Among many modifications and updates, the most significant change is that variable metadata is represented in a new structure.
This article was written to explain why there are so many Analysis Data Model (ADaM) documents and to help the ADaM user see how they have been designed to work together.
The current Immunogenicity Specimen Assessments (IS) domain in the SDTMIG v3.4 is designed to represent data pertaining to specimen-based assessments that measure the “presence, magnitude and scale of the immune response upon an antigen stimulation or encounter.” Not only does the new domain definition better align with the scientific definition of “immunogenicity”, but it also expands the scope of the IS domain from the previous versions of SDTMIG (i.e., v3.2 and v3.3), where the IS domain was defined to represent data pertaining to “assessments that describe whether a therapy provoked/caused/induced an immune response”.
Therapeutic Area User Guides (TAUGs) contain many useful examples, but it can be hard to find a useful example since there are over 40 TAUGs, and many TAUGs include examples that are useful outside a particular therapeutic area. The spreadsheet classifies TAUG examples by domain, so if a user has data that would be represented in a particular domain, the spreadsheet can identify TAUGs that might have examples relevant to their data.
When the Guidance for Ongoing Studies Disrupted by COVID-19 was being developed, one of the issues was how to represent subject visits, given that regulators wanted to know about visits that were missed or modified due to the pandemic.
The CDASHIG section "PE - Physical Examination" describes a best practice for collecting physical examination data. Basically, any abnormalities would be recorded as medical history or adverse events, depending on timing whether an exam was performed would be recorded by treating the exam as a procedure.
This article provides a good example for documenting study subject site transfers, using existing SDTMIG domains and minimal supplemental qualifiers. Originally modeled for COVID studies, this approach could be used any time a study subject change sites during their participation in the study.
Findings results as originally collected may not be review ready for a variety of reasons, so SDTM has a variable, --ORRES, for the result as originally collected, and another variable, --STRESC, for the result in ready-for-review form.
In all versions of the SDTMIG through v3.2, the "Conformance" section includes the following as a criterion for conformance:
If your data is based on a general observation class, you can determine the answer to this question by consulting the SDTM. Qualifiers for your general observation class, timing variables, and identifiers can generally be added to the dataset.
The earliest version of the SDTMIG had only one domain for tests on biologic specimens taken from a study subject, the Laboratory Test (LB) domain. SDTMIG v3.4 has 10 domains for specimen-based findings, plus the Biospecimen Events domain.
In an events or interventions domain, the variable --PRESP = "Y" can be used to indicate that the value in the topic variable (--TERM or --TRT) was pre-specified. However, --PRESP is not a variable that is allowed in findings domains.
In some cases, the reason for the restriction is fairly obvious, but in other cases, understanding the reason requires understanding the differences between how human clinical trials and nonclinical trials are conducted.
CDISC has published the first of a new kind of QRS supplement to the SDTMIG, a supplement for an oncology response criterion, Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1).