Administration of the test is automated to standardise the presentation of auditory and visual stimuli. The computer "speaks" all test instructions in order to minimise test variability.                                                                                                                                      .                                                                                                                                                                                                                        1. The I.V.A. is a 13 minute computerised test which combines two types of CPTs for both visual and auditory modalities. By combining impulsivity and inattention in a counter-balanced design and presenting each in the auditory and visual mode, the I.V.A. incorporates four CTPs into one.                                                                                                                                                     2.The test task is very simple and requires the person to click the mouse only when he hears or sees the target (in this case the number "1") and not to click when he sees or hears the non-target (foil) item (in this case the number "2").                                                                                                                                      3. The test contains two conditions in two modalities for a total of 200 trials.

The scores are divided into four primary diagnostic scale:  Response Control, Attention, Attribute and Validity.                                       .                                                                                                                                                                                                                                                                                                                                                                         1. Full Scale Response Control Quotient based on separate Auditory and Visual Response Control Quotient scores. The Response Control Quotient score are derived from visual and auditory Prudence, Consistency and Stamina scales.                                                                                                                                                                                                  .    A. Prudence: is a measure of impulsivity and response inhibition as evidenced by three different types of errors of commission (impulsivity, propensity and mode shift)                                                                                                                                                       .    B. Consistency : measures the general reliability and variability of the response times and is used to measure the ability to stay on task                                                                                                                                                                                                           .    C. Stamina : compares the mean reaction times of correct responses during the first 200 trials to the last 200 trials. This score is used to identify problems related to sustaining attention and effort over time.                                                                                                                                                 .                                                                                                                                                                                                                        .                                                                                                                                                                                                              2. Full Scale Attention Quotient is derived from separate Auditory and Visual Attention Quotients.The Attention Quotient scores are based on equal measures of visual and auditory Vigilance, Focus and Speed                                                                                                                                                                                  .   A. Vigilance : is a measure of inattention as evidenced by two types of different errors of omission (inattention ie failure to respond to a target when a response set of inhibition has been established and propensity i.e. non-response to a target immediately after a foil has been presented.)                                                                                                                                                  .   B. Focus : reflects the total variability of mental processing speed for all correct responses                                                                                                        .   C. Speed : reflects the average reaction time for all correct responses throughout the test and helps identify attention problems related to slow discriminatory mental processing.                                                                                                                                     .                                                                                                                                                                                                                      The Fine Motor Regulation scale provides additional information by recording off-task behaviours with the mouse, including multiple clicking, spontaneous clicks during instruction periods, anticipatory clicks and holding the mouse button down. In behavioural terms, the Fine Motor Regulation scale quantifies fidgetiness and restlessness associated with small motor hyperactivity.                                                                                                                                                                                                     .                                                                                                                                                                                                                        3. The Attribute scores provide information regarding the individual’s learning style:                                                                                                               .   A. Balance : indicates whether the individual processes information more quickly visually or aurally, or is equally quick in both modalities                                                                                                                                                                                                          .   B. Readiness : indicates whether the individual processes information more quickly when the demand is quicker or when it is slower. This scale also provides a subtle measure of inattention when the test taker just "can’t keep up" with the demand.                                                                                                                                                                                                        .                                                                                                                                                                                                                        4. There are three Validity scales used to evaluate whether a test taker’s responses can be interpreted in a meaningful way:                                                                                                                                                                                                         .   A. Comprehension : identifies random responding which would lead to faulty interpretation of other I.V.A. scale scores. Research has shown this to be the single most sensitive sub-scale in discriminating ADHD                                                                                                                                                                                 .   B. Persistence : is a measure of motivation when the individual is asked to do "one more thing". It can also reflect mental or motor fatigue                                                                                                                                                                                                     .   C. The Sensory / Motor : scales are used to rule out neurological, psychological or learning problems as evidenced by slow simple reaction time.

Validity research using the IVA CPT with children ages 7 to 12 had a sensitivity of 92% in identifying individuals diagnosed by a clinician as having ADHD. The IVA CPT also correctly identified the 90% of non-ADHD children (i.e., false positives = 10%). Another validity study for a typical mixed age clinical population (ages 6 to 55) found that as part of a clinician’s comprehensive psychological evaluation, the combination of the ADHD rating scale data with the IVA CPT matched the clinical diagnosis 90% of the time. In addition, this study did not misclassify 89% of individuals who did not have ADHD (i.e., 11% false positives).