Base SAS

CDISC Procedure for the CDISC SDTM 3.1 Format

Overview

Support for CDISC SDTM 3.1 data validation is a recent feature addition to the CDISC procedure. PROC CDISC now provides data content checking against the domain definitions provided by the SDTM. This document explains how to use PROC CDISC for CDISC SDTM.

Previously, PROC CDISC supported only the CDISC ODM 1.2 format. For complete PROC CDISC usage and syntax documentation for CDISC ODM, see CDISC Procedure for CDISC ODM 1.2 Format.

Understanding the SDTM Standard

Whereas the ODM standard defines both a data model and its expression mechanism via XML, the Study Data Tabulation Model (SDTM) is a data content only standard.

The SDTM defines a standard structure for study data tabulations that are to be submitted as part of a product application to a regulatory authority such as the United States Food and Drug Administration (FDA). The SDTM was prepared by the CDISC Submission Data Standards (SDS) Team to guide the organization, structure, and format of tabulation data sets for study data submitted to regulatory authorities. Data tabulation data sets are one of four ways to represent the human subject Case Report Tabulation (CRT) and equivalent animal data submitted to the FDA.

The SDTM is composed of 23 defined domains within six broad categories. The model also provides the ability to create custom-defined domains with sets of standard variable definitions. Variables in common across domains all have similar name extensions, and the standard specifies the beginning prefix of all variables be a (typically) two-letter domain abbreviation.

PROC CDISC for SDTM 3.1 Format

Syntax

The PROC CDISC syntax for CDISC SDTM is presented below. The DATA= parameter specifies the location of your SDTM conforming data source.

PROC CDISC        MODEL=SDTM
                  ;

SDTM              SDTMVersion = "3.1"
                  ;

DOMAINDATA        DATA = results.AE
                  DOMAIN = AE
                   CATEGORY = EVENTS
                  ;
RUN;

Supported SDTM 3.1 Domains

The CDISC procedure currently supports 15 of the 23 SDTM domains. The Trial Design Components comprise the majority of unsupported remainder of the list. Values for the domain and category parameters are taken from the table as depicted below:

Supported SDTM 3.1 Domains	DOMAIN=	CATEGORY=
Demography	DM	Special
Comments	CO	Special
Concomitant Medications	CM	Interventions
Exposure	EX	Interventions
Substance Use	SU	Interventions
Adverse Events	AE	Events
Disposition	DS	Events
Medical History	MH	Events
ECG Test Results	EG	Findings
Inclusion/Exclusion Exception	IE	Findings
Laboratory Test Results	LB	Findings
Physical Examinations	PE	Findings
Questionnaires	QS	Findings
Subject Characteristics	SC	Findings
Vital Signs	VS	Findings

CDISC Procedure Capabilities

PROC CDISC performs the following checks on domain content of the source:

Verifies that all required variables are present in the data set
Reports as an error any variables in the data set that are not defined in the domain
Reports a warning for any expected domain variables that are not in the data set
Notes any permitted domain variables that are not in the data set
Verifies that all domain variables are of the expected data type and proper length
Detects any domain variables that are assigned a controlled terminology specification by the domain and do not have a format assigned to them.

The procedure also performs the following checks on domain data content of the source on a per observation basis:

Verifies that all required variable fields do not contain missing values
Detects occurrences of expected variable fields that contain missing values
Detects the conformance of all ISO-8601 specification assigned values; including date, time, datetime, duration, and interval types
Notes correctness of yes/no and yes/no/null responses,

With the exception of yes/no and yes/no/null content just noted, the current procedure implementation does not validate the content of controlled terminology responses against a list of acceptable values. An update planned later this year will provide a mechanism for "reversing an assigned format," but currently only the absence/presence of a format is used as the conformance indicator for controlled terminology field content.

Implementation Notes

The SDTM addition to PROC CDISC does not convert existing SDS 2.x content to SDTM 3.x representations.
PROC CDISC does not automatically generate the V5 XPORT file from the data source.

FOCUS AREAS