Table 1

Description and calculation of domain scores for CNS vital signs

Clinical domainTestDomain score calculationDomain description
Psychomotor speedFTT, SDCFTT total taps average +SDC correct responsesAbility to perceive, attend and respond to complex visual–perceptual information and perform simple fine motor tasks.
Reaction
time
ST(ST complex reaction time correct+ST reaction time correct)/2Speed of reaction to a simple and increasingly complex set of directions.
Complex attentionCPT, SAT, STST commission errors+SAT errors+CPT errorsAbility to track and respond to a variety of stimuli over lengthy periods of time and/or perform complex mental tasks requiring vigilance quickly and accurately.
Cognitive flexibilitySAT, STSAT correct responses−SAT errors−ST commission errorsAbility to adapt to a rapidly changing and increasingly complex set of directions and/or to manipulate the information.
Processing speedSDCSDC correct responses−SDC errorsAbility to recognise and process information, that is, perceiving/ responding to incoming information, motor speed, fine motor coordination, visual–perceptual ability.
Verbal
memory
VBMCorrect hits and passes immediate+correct hits and passes delayAbility to remember (recognise and retrieve) words.
Visual
memory
VIMCorrect hits and passes immediate+correct hits and passes delayAbility to remember (recognise and retrieve) geometric figures.
  • CPT, Continuous Performance Test; FTT, Finger Tapping Test; SAT, Shifting Attention Test; SDC, Symbol Digit Coding Test; ST, Stroop Test; VBM, Verbal Memory Test; VMT, Visual Memory Test.