Section 2.1 of the Analysis
Data Model Implementation Guide provides the fundamental
principles of the CDISC ADaM model.
-
Analysis data sets and associated
metadata must clearly and unambiguously communicate the content and
source of the data sets supporting the statistical analyses performed
in a clinical study.
-
Analysis data sets and associated
metadata must provide traceability to enable an understanding of where
an analysis value came from.
-
Analysis data sets must be readily
usable with commonly available software tools.
-
Analysis data sets must be associated
with metadata to facilitate clear and unambiguous communication. Ideally,
the metadata is machine-readable.
-
Analysis data sets should have
a structure and content that enable statistical analyses to be performed
with minimal programming. Such data sets are described as analysis-ready.
Implementation of the
CDISC ADaM 2.1 reference standard in the SAS Clinical Standards Toolkit
supports each of these principles.
The number and structure
of analysis data sets are highly dependent on the type of study, the
study objectives as defined in the statistical analysis plan, and
discussions with the reviewing authority. ADaM data sets incorporate
derived and collected data that permit analysis with little or no
additional programming. Data can be from various SDTM domains, other
ADaM data sets, or any combination thereof.
The CDISC ADaM 2.1
reference standard currently supports these analysis data set structures:
-
The subject-level analysis data
set (ADSL) provides descriptive information about subjects, such as
study disposition, demographic, and baseline characteristics. The
ADSL is the primary source for subject-level variables included in
other analysis data sets, such as population flags and treatment variables.
There is only one ADSL per study, and the ADSL and its related metadata
are required in each CDISC-based submission of data from a clinical
trial, even if no other analysis data sets are submitted.
-
The ADaM Basic Data Structure (BDS)
is used for the majority of ADaM data sets, regardless of the therapeutic
area or type of analysis. Each BDS data set contains one or more records
per subject and analysis parameter. The structure of some BDS data
sets might include an analysis time point. A record in a BDS analysis
data set can represent an observed, derived, or imputed value required
for analysis. Each BDS data set contains a core set of variables that
describe the analysis parameter and the value being analyzed. A data
value can be derived from any source file, including any combination
of SDTM and ADaM data sets. The Time-to-Event analysis data set is
an example implementation of the BDS structure.
-
The Adverse Event analysis data
set (ADAE) structure is built on the nomenclature of the CDISC SDTM
Implementation Guides for collected data. The ADAE data set adds attributes,
variables, and data structures that are required for statistical analyses.
The primary SDTM source domain for the ADAE data set is AE, with the
corresponding SUPPAE. Additional variables can be added from the ADaM
ADSL data set. The ADAE data set is required when SDTM AE is not sufficient
to support all adverse event analyses. The ADAE structure for the
standard adverse event safety data set has at least one record per
each AE recorded in the SDTM AE domain.
Metadata for the ADSL,
BDS, and ADAE data sets is defined in the SAS Clinical Standards Toolkit
reference_tables data set in the standard metadata folder.
The Analysis Data Model
identifies four types of metadata that are captured and supported
by the SAS Clinical Standards Toolkit.
ADaM Metadata Types and SAS Clinical Standards Toolkit Locations
|
|
SAS Clinical Standards
Toolkit Location
|
Analysis data set metadata
|
global standards library
reference_tables.sas7bdat
|
Analysis variable metadata
|
global standards library
reference_columns.sas7bdat
|
Analysis parameter-value-level
metadata
|
global standards library
valuemetadata.sas7bdat template
sample library metadata
source_values.sas7bdat example
|
Analysis results metadata
|
global standards library
analysis_results.sas7bdat template
sample library metadata
analysis_results.sas7bdat example
|
Version 1.0 of the Analysis
Data Model Implementation Guide (ADaMIG) defines a common set of ADSL
and BDS columns that can be used as templates for ADaM analysis data
sets. This set of ADSL and BDS columns has been supplemented with
Version 1.0 of the Analysis Data Model (ADaM) Data Structure for Adverse
Event Analysis. Metadata for the 290 columns in the SAS representation
of ADSL, BDS, and ADAE is defined in the SAS Clinical Standards Toolkit
reference_columns data set in the standard metadata folder. Empty
ADSL, BDS, and ADAE data sets containing these columns can be derived
from the SAS Clinical Standards Toolkit global standards library using
the utility macro cst_createTablesForDataStandard.
The SAS Clinical Standards
Toolkit CDISC ADaM reference standard also provides metadata and code
to validate the structure and content of the ADaM analysis data sets.
To enable validation,
supplemental files supporting ADaM validation processes include these
SAS Clinical Standards Toolkit global standards library files:
-
The Validation Master data set
in the
validation/control folder contains
the superset of checks validating the structure and content of each
analysis data set. These checks are based on versions 1.1 and 1.2
of the CDISC ADaM Validation Checks as prepared by the CDISC ADaM
team, as well as selected checks that are unique to the SAS Clinical
Standards Toolkit.
-
The Messages data set in the
messages folder
provides error messaging for all Validation Master checks.
-
SAS code in the
macros folder
provides code that is specific to ADaM that augments code that is
provided in the primary SAS Clinical Standards Toolkit autocall library
(
!sasroot/cstframework/sasmacro).
These supplemental files,
in whole or in part, define the SAS Clinical Standards Toolkit CDISC
ADaM reference standard.