Symbol Digit Modalities Test (SDMT)

Purpose: Screen for organic cerebral dysfunction in both children and adults

Age: 8+ years of age

Time: 5 minutes

Administration: Individual and group

The Symbol Digit Modalities Test (SDMT) detects cognitive impairment. Administered in just 5 minutes, it is an ideal way for busy clinicians to screen for organic cerebral dysfunction in both children (8 years and older) and adults.    

The test involves a simple substitution task that normal children and adults can easily perform. Using a reference key, the examinee has 90 seconds to pair specific numbers with given geometric figures. Responses can be written or oral.

The SDMT has demonstrated remarkable sensitivity in detecting not only the presence of brain damage, but also changes in cognitive functioning over time and in response to treatment - individuals with cerebral dysfunction perform poorly on the SDMT, in spite of normal or above-average intelligence.