If you are transitioning into clinical data programming or pharmaceutical statistical analysis, understanding the CDISC standards is essential. The two primary data standards you will work with every day are SDTM and ADaM.
What is SDTM (Study Data Tabulation Model)?
SDTM is the standard format for representing clinical trial raw data collected on Case Report Forms (CRFs) and electronic data capture (EDC) systems. SDTM is observation-level and standardized across all sponsors.
- DM: Demographics (one record per subject)
- AE: Adverse Events (one record per event occurrence)
- VS: Vital Signs (one record per measurement per visit)
- LB: Laboratory Tests
What is ADaM (Analysis Data Model)?
ADaM datasets are derived directly from SDTM. They are specifically structured to generate statistical Tables, Listings, and Figures (TLFs) for FDA and EMA regulatory submissions without complex transformations inside reporting procedures.
"SDTM captures what happened to the patient. ADaM structures the data so statisticians and programmers can analyze the clinical efficacy and safety."
Key Differences at a Glance
Feature SDTM ADaM
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Purpose Standardized raw data Statistical analysis & TLFs
Target Audience Data Managers & Reviewers Biostatisticians & Regulators
Subject Dataset DM ADSL (Subject-Level Analysis)
Event Dataset AE ADAE (Analysis Adverse Events)
Derivations Minimal (raw-aligned) Heavy (baselines, flags, changes)How ADSL Forms the Backbone of All Clinical Analyses
Every clinical project begins with ADSL (Subject-Level Analysis Dataset). ADSL contains critical analysis population flags such as SAFFL (Safety Population Flag) and ITTFL (Intent-to-Treat Flag), treatment start/end dates, and demographic baseline variables.