Integrated Visual & Auditory Continuous Performance Test
IVA is a unique combined auditory and visual continuous performance test designed to help the clinician make an accurate diagnosis of ADHD. Following the diagnostic criteria outlined in the DSM-IV, IVA provides data to help the clinician diagnose and differentiate between the four sub-types of Attention-Deficit/Hyperactivity Disorder -- ADHD Predominantly Inattentive Type (formerly called ADD), ADHD Predominantly Hyperactive-Impulsive Type, ADHD Combined Type, and ADHD Not Otherwise Specified.
The main test task, which lasts approximately thirteen minutes, presents 500 trials of "1"s and "2"s in a pseudo-random pattern requiring the shifting sets between the visual and auditory modalities. The subject is required to click the mouse only when he sees or hears a 1 and to inhibit clicking when he sees or hears a 2. During some segments of the test, the 1s are more common than the 2s, creating a response set which "pulls" for errors of commission, or impulsivity. During alternating segments of the test the 1s occur rarely; this invites more errors of omission, or inattention, since the subject must remain vigilant while he waits for a 1 to occur.
All scores are presented both as raw scores and as quotient scores. The basis for statistical analysis is the same as that used for most IQ tests; all quotient scores have a mean of 100 and a standard deviation of 15. Applying these familiar interpretative guidelines makes it easy for you to interpret test results.
IVA’s scores are divided into four categories — Attention, Response Control, Attribute and Validity. The primary diagnostic scales are the Full Scale Response Control Quotient and Full Scale Attention Quotient scores.
The Full Scale Response Control Quotient is based on separate Auditory and Visual Response Control Quotient scores.
These Response Control Quotient scores are derived from visual and auditory Prudence, Consistency and Stamina scales.
1) Prudence is a measure of impulsivity and response inhibition as evidenced by three different types of errors of commission.
2) Consistency measures the general reliability and variability of response times and is used to help measure the ability to stay on task.
3) 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.
The 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.
1) Vigilance is a measure of inattention as evidenced by two different types of errors of omission.
2) Focus reflects the total variability of mental processing speed for all correct responses.
3) Speed reflects the average reaction time for all correct responses throughout the test and helps identify attention processing problems related to slow discriminatory mental processing.
The Fine Motor Regulation scale provides additional information by recording off-task behaviors with the mouse, including multiple clicks, spontaneous clicks during instruction periods, anticipatory clicks and holding the mouse button down. In behavioral terms, the Fine Motor Regulation score quantifies fidgetiness and restlessness associated with small motor hyperactivity.
IVA’s Attribute scores provide you with data regarding the client’s learning style. These scales are:
1) Balance — indicates whether the test taker processes information more quickly visually or aurally, or is equally quick in either modality.
2) Readiness — indicates whether the test taker processes information more quickly when the demand is quicker or when it is slower. This scale can provide a subtle measure of inattention when the test taker just “can’t quite keep up” with the demand.
IVA’s Validity scales are auditory and visual Comprehension, Persistence and Sensory/Motor.
1) Comprehension identifies random responding, which would lead to faulty interpretation of other IVA scale scores. Research has shown this to be the single most sensitive sub-scale in discriminating ADHD.
2) Persistence is a measure of motivation when the test taker is asked to do “one more thing.” It can also reflect motor or mental fatigue.
3) The Sensory/Motor scales are used to rule out possible neurological, psychological or learning problems as evidenced by slow simple reaction time.
IVA’s normative group (N=1700) is divided by gender, and grouped by age as follows: 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17-18, 19-21, 22-24, 25-29, 30-34, 35-39, 40-44, 45-54, 55-65, 66-96. The database was primarily collected in Richmond, Texas, Michigan, California and Florida. All individuals were excluded who were in therapy, had a history of LD, hyperactivity or attention problems, who were on any type of medication (other than birth control unless >55 years of age), who had a history of neurological problems (dementia, stroke or TBI) and those who could not validly complete the test. A relatively equal number of males and females were included in each age/sex group and an effort was made to have about 30 males and 30 females in each age group though this was not always possible. At about 30 in each group, the standard error ranged between 3-4 points on a standard scale for all the scales. Many different ethnic groups were included in the normative sample, but this data has not been broken down. The normative data is available in the IVA program sub-directory and can be used in most cases to manually calculate the standard scores, except when the standard deviation is small and the percent raw score reported in the reports has been rounded before being displayed (mainly an issue with young adults who make few errors.)
1) IVA saves you time. IVA enables you to measure and evaluate both auditory and visual inattention and impulsivity separately and simultaneously in less than 20 minutes.
2) IVA provides you with wealth of objective data. Following the guidelines of the DSM-IV for the diagnosis of ADHD , IVA's unique integrated format provides provides much more information than can be drawn from subjective rating scales or from any other commercially available CPT.
3) IVA improves your diagnostic accuracy. In a validity study, IVA correctly identified clinician diagnosed ADHD children 92.3% of the time and had a low positive rate of 10%.
4) IVA helps you communicate your case to parents, teachers and other clinicians. IVA's visual graphs give skeptics a clear, concrete picture of measurable data to support your diagnosis.
5) IVA gives you unique insight. IVA's Attribute scales provide you with perceptions regarding learning styles and tell you whether your client is a visual or auditory learning.
6) IVA is easy to administer. All test instructions are presented by the computer both visually and aurally. IVA's natural-sounding voice provides a highly structured, standardized, easy-to-use administration procedure.
7) IVA is easy to interpret. Using the same type of scoring system as IQ test, IVA's interpretation is familiar to clinicians and easy to learn.
8) IVA helps you objectively assess your clinical results. Research studies demonstrate excellent test-retest reliability and stability, making IVA a useful instrument for measuring treatment and medication effects.
9) IVA can help you screen for possible emotional and neurological problems. IVA's Validity scales tell you if your client is responding randomly or abnormally slowly. (IVA's response time measure is accurate + or - 8 ms.)
10) IVA doesn't keep you waiting. The test provides immediate analysis - no need for you ever to mail in anything. In addition, IVA stores all raw data so future analyses based on research may be applied to previously collected data.