- The first reported symbol digit substitution task was described in 1913.
- Aaron Smith and colleagues began piloting and using the Symbol Digit Modalities Task (SDMT) in the early 1960s.
- The SDMT was copyrighted by Western Psychological Services (in 1973, 1976, and 1982), and the most recent (15th) printing of the manual was in 2017.
- The SDMT has been submitted to the FDA COA Qualification Program
Instrument copyrighted by WPS
To screen cerebral dysfunction or learning disorders in children and adults
To assess spontaneous recovery of cerebral functions as well as improvement resulting from specific therapeutic regimes
- Nervous System Diseases
- Mental Disorders
- Pathological Conditions, Signs and Symptoms
Generic for Mental Disorders
Type of Clinical Outcome Assessment (COA)
Bibliographic reference(s) of the original questionnaire
Smith A. Symbol Digit Modalities Test (Manual). Western Psychological Services. 1973 (WPS Website)