Conners' Continuous Performance Test II (CPT II V.5)
This report is intended to be used by the test administrator as an interpretive aid. This report should notbe used as the sole basis for clinical diagnosis or intervention.
IntroductionThe Conners’ Continuous Performance Test II (CPT II) is a valuable assessment tool that can revealimportant information about an individual’s functioning. The instrument is helpful when a diagnosis ofADHD is being considered.This report provides information about Jane’s CPT II scores, what scales and indexes are elevated andhow she compares to the normative group. The non-clinical sample includes 1,920 individuals from thegeneral population. The clinical norm groups include 378 cases with ADHD, and 223neurologically-impaired adults. For further information refer to the CPT II Technical Guide and SoftwareManual published by MHS.
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Note: Hit RT is scaled such that for1. Inattentiveness - slow reaction times produce high T-scores.2. Impulsivity - fast reaction times produce high T-scores.
Percentile99
98
84
50
3
1
16
The following graph compares Jane's T-scores against Non-Clinical and ADHD norms.
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Confidence Index Associated with ADHD AssessmentThe following graph shows Jane's Confidence Index for the clinical and non-clinical profiles.
The CPT discriminant function indicates that the results better match a non-clinical than clinical profile.The Confidence Index computed can be readily described in the following way: The chances are 85.81out of 100 that no significant attention problem exists.
Non-clinical, 85.81% Confidence
The Confidence Index should always be reviewed in relation to results on the remaining CPT IImeasures. When the Confidence Index falls close to 50 (providing no decision), however, there is aheightened need to examine all individual index and measure scores, and to consider theinter-relationships between them.
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Summary of Overall MeasuresThe following table summarizes Jane's overall measures and gives general information about how shecompares to the normative group.
(general population norms used)
Percentile GuidelineT-ScoreValueMeasure21.89 good performance42.231
0.31Omissions%
16.57 good performance40.2814 38.89
Commissions%
8.09 a little fast36.01344.93Hit RT14.60 good performance39.455.73Hit RT Std. Error30.70 good performance43.9610.90Variability33.29 good performance44.680.61Detectability (d')26.25 mildly atypical42.640.23Response Style (ß)34.39 good performance44.980
0.00Perseverations%
6.16 very good performance33.57-0.03Hit RT Block Change1.36 very good performance26.89-0.15Hit SE Block Change
53.63 within average range49.910.08Hit RT ISI Change84.97 MILDLY ATYPICAL60.370.30Hit SE ISI Change
Summary of Inattention MeasuresThe following table summarizes Jane's inattention measures and gives general information about howshe compares to the normative group.
Summary of Impulsivity MeasuresThe following table summarizes Jane's impulsivity measures and gives general information about howshe compares to the normative group.
Summary of Vigilance MeasuresThe following table summarizes Jane's vigilance measures and gives general information about howshe compares to the normative group.
(general population norms used)
Percentile GuidelineT-ScoreValueMeasure6.16 OK33.57-0.03Hit RT Block Change1.36 OK26.89-0.15Hit SE Block Change
About the Summary MeasuresConversions were made for d' so that high T-scores (i.e., >= 60) indicate poor performance for ALLmeasures listed in the table.For B, both high AND low scores are noteworthy, indicating unusual response styles. Likewise, both high and low Hit RT T-scores can be significant. Low T-scores (unusually fast RTs) maybe associated with impulsivity, and high T-scores (unusually slow RTs) may indicate inattentiveness.In general, the more measures that are atypical, the more likely that a problem exists. The presence ofonly one atypical measure does not usually indicate a problem.
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Interpretive GuideThe CPT II provides a rich source of information. The report includes four sections. The first sectionchecks the validity of the administration. The second section defines the measures and summarizes therespondent's performance on each measure. The third section synthesizes the information from themeasures into a performance profile and provides substantive analysis. The fourth section usesdiscriminant analyses to provide an overall assessment, which is summarized briefly in the QuickViewsection presented next.
QuickViewRespondent: Jane SampleConfidence Index Assessment (ADHD): Non-clinical, Confidence Index = 14.19% (i.e., 85.81%confidence of non-clinical classification)Non-clinical for Attention Deficit, Confidence Index = 14.19% (i.e., 85.81% confidence of non-clinicalclassification). The CPT discriminant function indicates that the results better match a non-clinical thanan ADHD clinical profile. The Confidence Index can be described in the following way. The chances are85.81 out of 100 that no clinical attention problem exists.
Validity of AdministrationThe CPT II performs a self-diagnostic check of the accuracy of the timing of each CPT administration.There was no indication of any timing difficulties or respondent non-compliance, and the currentadministration should be considered valid.
In addition to the Confidence Index, the scores for all of the other specific measures must be consideredwhen interpreting the results.
Definitions and Summary of MeasuresThis section defines each measure, and provides a brief statement regarding the respondent'sperformance with respect to each of these measures. Substantive interpretation is then provided insubsequent sections.OmissionsOmissions result from the failure to respond to target letters (i.e., non-Xs)Jane made fewer omission errors than the average of the normative group.CommissionsCommission errors are made when responses are given to non-targets (i.e., Xs).Jane made few commission errors. The percentage of commission errors is lower than the average ofthe normative group.Hit Reaction Time - Overall (Hit RT)Overall Hit Reaction Time is the average speed of correct responses for the entire test.Jane's Overall Mean Reaction Time was fast in comparison to the normative group average.Standard Error - Overall (Hit RT Std Error)Standard Error is a measure of response speed consistency. The higher the Overall Standard Error, thegreater the inconsistency in the response speed.Jane's reaction times were less variable than the normative group average. Reaction times were highlyconsistent.
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Variability of Standard ErrorLike Overall Standard Error, the Variability of Standard Error is a measure of response speedconsistency. However, Variability of Standard Error measures "within respondent" variability. That is, theamount of variability the individual shows in 18 separate segments of the test in relation to his or herown overall standard error. Although Variability of Standard Error is a different measure than OverallStandard Error, typically the two measures produce comparable results. The higher the Variability ofStandard Error, the greater the inconsistency in the response speed.The Variability of Standard Error for Jane was lower than the normative group average.Detectability (d')The value d' is a measure of the difference between the signal (non-X) and noise (X) distributions. Assuch d' provides a means for assessing an individual's discriminative power since, in general, thegreater the difference between the signal and noise distributions, the better the ability to distinguish anddetect X and non-X stimuli.Jane had a relatively low T-score for d-prime indicating better than average detectability.Response Style Indicator (ß)Beta (ß) represents an individual's response tendency: Some individuals are cautious and choose not torespond very often. Conceptually, such individuals want to make sure they are correct when they give aresponse. Higher values of Beta reflect this response style. The emphasis is on avoiding commissionerrors. Other individuals respond more freely to make sure they respond to most or all targets, and theytend to be less concerned about mistakenly responding to a non-target. Lower values of Beta areproduced by this response style.The obtained value of Beta is lower than the average of the normative group. Jane's response style wassomewhat different than that of a typical respondent from the norm group.PerseverationsAny reaction time that is less than 100 ms constitutes a perseverative response. Given normalexpectations of physiological ability to respond, such responses are usually either slow responses to apreceding stimuli, a random response, an anticipatory response, or a response repeated withoutconsideration of the stimuli or task requirements.The percentage of perseverations was lower than the average of the normative group.Hit Reaction Time by Block (Hit RT Block Change)Hit RT Block Change measures change in reaction time across the duration of the test. High values ofHit RT Block Change indicate a substantial slowing in reaction times. Low values indicate thatresponses got quicker as the test progressed.The low T-score on this measure indicates that Jane did an exceptionally good job of sustaining herreaction time over the duration of the test.Standard Error by Block (Hit SE Block Change)Standard Error by Block detects changes in response consistency over the duration of the test.High values of Hit SE Block Change indicate a substantial loss of consistency as the test progressed.Low values on this measure indicate sustained or improved response consistency.The low T-score on this measure indicates that Jane became more consistent in reaction time as thetest progressed.
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Reaction Time by Inter-Stimulus Interval (Hit RT ISI Change)This measure examines change in average reaction times at the different Inter-Stimulus Intervals (i.e.,when the letters are presented at 1, 2, or 4 sec. intervals).The obtained value of Hit RT ISI Change is within the average range of the normative group indicatingtypical changes in response speeds across the different Inter-Stimulus Interval levels.Standard Error by Inter-Stimulus Interval (Hit SE ISI Change)This measure examines change in the standard error of reaction times at the different Inter-StimulusIntervals (i.e., when the letters are presented at 1, 2, or 4 sec. intervals).The high T-score on this measure indicates that Jane showed less consistency in reaction times at thedifferent Inter-Stimulus Intervals than was typical in the norm group. Sometimes, this finding relates toactivation/arousal needs. Consider optimal stimulation levels in explaining performance.
Profile AnalysisThis section integrates all of the CPT data obtained from the administration to provide clinically relevantinterpretations of the results. The interpretations given in this section should be treated as hypotheses,and must be combined with other information about the respondent.Jane's responses were very fast and she also made relatively few errors. Therefore, the fast speedprobably represents fast processing ability.* Jane's CPT performance was substantively affected by the Inter-Stimulus Interval. Specifically,responses became more erratic when the ISI was slowed from 1 second to 2 and 4 seconds. Thedifficulty making the necessary adjustment to the change in tempo of stimulus presentation may reflectlimitations in the ability to adjust to changes in task demands.In addition, each score can also be considered separately concentrating on T-scores above 60 (if thereare any). High scores in Omissions, Commissions, and Overall Hit Reaction Time pertain toinattentiveness. High scores on Overall Standard Error and Variability relate to response consistencyand “erraticness.” A high T-score for d' is commonly associated with poor perceptual power for this taskand a below average ability to discriminate targets from non-targets. High scores on either Hit RT ISIChange or Hit SE ISI Change tend to indicate a difficulty to adjust to changing task demands. Highcommission T-scores can be the result of inattentiveness, but when coupled with average or faster thanaverage reaction times (e.g., Overall Hit RT T-score of 50 or less), it also can be due to impulsivity. Highscores on either Hit RT Block Change or Hit SE Block Change result from a decline in performance asthe test progressed, and high scores on these measures may relate to vigilance deficits.
Overall AssessmentThis section looks at the Confidence Index and the number of elevated measures to provide an overallassessment of performance on the CPT.ADHD Assessment: CPT Performance Good; No indication of attention problems.The ADHD Confidence Index suggests non-clinical classification, and few or none of the measures wereelevated significantly.Important Additional Notations
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The comments in this report are based on general patterns apparent in Jane Sample's responses.Always examine the graphs and information provided carefully to refine (and add to) the interpretationsgiven. For instance, you will want to consider the statistics that are not explicitly discussed in this printedreport. Please consult the CPT II Technical Guide and Software Manual, or use the CPT II Help whileexamining "on screen" report for information about the statistics.The comments made in this report should be used as an aid in the assessment process. Other sourcesof information (e.g., historical information, assessments, observations) should be used in conjunctionwith the information from the CPT II reports when assessing an individual. The information contained inthis report should be treated as confidential.
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Highly AtypicalModerately Atypical
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<=
Highly AtypicalModerately Atypical
Mean Hit Reaction Times - ISI Collapsed(general population norms used)
Hit Standard Errors - ISI Collapsed(general population norms used)
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Highly AtypicalModerately Atypical
>=Highly Atypical
Moderately Atypical
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Hit Standard Errors - ISI Expanded(general population norms used)
Mean Hit Reaction Times - ISI Expanded(general population norms used)
