The Most Representative CPT Normative Samples Collected
The new normative sample consists of 1,400 cases and is representative of the United States (U.S.) population in terms of key demographic variables such as gender, race, geographical region, and parental education level.
Reliability Users can be confident that the Conners CPT 3 will yield consistent and stable scores across administrations.
One measure of a test’s internal consistency is split-half reliability, which has been previously used to establish the reliability of other continuous performance tests. Split-half reliability estimates of the Conners CPT 3 scales were calculated for the normative and clinical samples. Results were very strong – across all sccores, the median split-half reliability estimate was .92 for the norm samples, and .94 for the clinical samples (all correlations were significant, p < .001). These results indicate that the Conners CPT 3 demonstrates excellent internal consistency for both the normative and the clinical groups.
Test-retest reliability refers to the consistency of scores obtained from the same respondent on separate occasions over a specified period of time. To estimate the test-retest reliability of the Conners CPT 3, a sample of 120 respondents from the general population completed the Conners CPT 3 twice with a 1- to 5-week interval between administrations. The median test-retest correlation was .67. These results suggest a good level of test-retest reliability.
Validity Users can be assured that the Conners CPT 3 will help detect attention deficits and differentiate Clinical from Non-Clinical Cases.
Discriminative validity pertains to an instrument’s ability to distinguish between relevant participant groups (i.e., the test’s ability to differentiate between clinical and non-clinical groups). In order to conduct discriminative validity analyses, Conners CPT 3 data were collected during the standardization process from 346 children and adults who had an existing ADHD diagnosis. Conners CPT 3 scores from this ADHD sample were compared to a matched sample from the general population. Results indicated that significant differences were found between the ADHD sample and the matched general population sample on most measures with small to moderate effect sizes (d = 0.10 to 0.49). As expected, the ADHD sample performed more poorly (i.e., they had higher scores on the Conners CPT 3). In particular, the ADHD sample had lower d’ scores, indicating more difficulty in distinguishing between relevant stimuli and distractors. Similarly, the ADHD sample made a greater number of errors (i.e., they had higher percentages of Omissions, Commissions and Perseverations than did the general population sample) and showed more variability in their responses overall (i.e., higher HRT SD scores) and across subblocks (i.e., higher Variability scores) compared to the matched sample of general population. The responses of the ADHD sample were also affected more by changes in block and ISI (i.e., higher HRT Block Change and HRT ISI Change scores).
Another approach in establishing the Conners CPT 3’s validity is to show how it works together with other measures of similar constructs in the assessment of attention problems. To assess such validity, samples were collected in which cases were scored on the Conners CPT 3 and another measure of attention. Specifically, in a sample of 112 non-clinical and ADHD youths, parent-reports on the Conners 3rd Edition (Conners 3-P; Conners, 2008) were collected in addition to their scores on the Conners CPT 3. In a second sample of 137 non-clinical and ADHD adults, self-reports on the Conners Adult ADHD Rating Scales (CAARS; Conners, Erhardt, & Sparrow, 1999) were collected in addition to their scores on the Conners CPT 3. Logistic regressions were conducted in order to determine how well scores from the Conners CPT 3 improve the diagnostic efficacy of the rating scales in predicting group membership into ADHD or general population groups. For youth, when the Conners 3-P and Conners CPT 3 scores were considered together, there was an overall correct classification rate (i.e., the ability to accurately predict group membership) of 88.4%, sensitivity (i.e., the ability to correctly detect ADHD cases) of 89.5%, and specificity (i.e., the ability to correctly detect general population cases) of 87.3%. These values were 4.5%, 3.5%, and 5.5%, respectively, higher than when the rating scale was used on its own. For adults, when the CAARS and Conners CPT 3 scores were considered together, the overall correct classification rate was 92.7%, sensitivity was 73.1%, and specificity was 97.3%. These values were 3.6%, 7.7%, and 2.7%, respectively, higher than when the rating scale was used on its own. These results indicate that adding the Conners CPT 3 to scores from rating scales increases the ability to predict group membership. Back to the top
The computer-generated scoring reports have been re-designed to better guide assessors through each step of the recommended interpretation process.
There are two report types available:
- Updated with a new easy to follow look and feel.
- Interpret the data more efficiently with the addition of clear visuals.
- More interpretive text to complement and narrate the wealth of data.
- Easy to understand Clinical Likelihood Statements are based on the number of atypical T-scores to estimate the likelihood of a clinical disorder.
- Assessment Report, which provides detailed results from a single administration
- Progress Report, which provides an overview of change over time by combining and comparing results of up to four administrations.
Back to the top C. Keith Conners, Ph.D.
Dr. C. Keith Conners has had an extraordinary and diverse career as an academic, clinician, researcher, lecturer, author, editor-in-chief, and administrator. His dedication to the study of ADHD and other childhood problems propelled him to the forefront of his field. His intense interest has led him to write several books, journal articles, and book chapters based on his research on ADHD and childhood disorders. He is highly recognized in the field of psychology for his numerous contributions
During the course of his career, Dr. Conners was greatly intrigued by children exhibiting a diverse pattern of symptoms. He collected data on children from the general population and children with an existing symptom list who were referred to clinics, and eventually published the first version of the Conners’ Parent Rating Scale. The increasing use and popularity of the rating scales eventually made his original articles among the most cited in the literature on the subject.
Dr. Conners is now retired and is currently residing in North Carolina. He continues to lecture, present workshops on diagnosis and assessment, and serve as a consultant to numerous government and private organizations.
The Conners 3rd Edition™ (Conners 3™) and the Conners Comprehensive Behavior Rating Scales™ (Conners CBRS™) represent Dr. Conners’ life-long commitment to integrating the latest in academic research with contemporary clinical practice. Back to the top