Presentation and Evaluation of Standardization
The NEPSY was first developed in 1980 and released in Finland. It was not until 1998, after it was revised by its current authors Korkmaan, Kirk, and Kemp, that it was released in the United States. The current edition, the NEPSY-II, was published in 2007 (McGrath, 2014). With the publication of the second edition, new standardizations were required. Participants included 200 nation-wide examiners who had experience administering the NEPSY and had a specific population of examinees (Korkman, et al., 2007a). Overall, 1,200 individuals (an even distribution of females and males) were randomly assigned to each examiner. These ...view middle of the document...
The standard measure of error was developed to compare an examinee’s score with their true score. These measurements can be found in Table 4.3 of the NEPSY-II Clinical and Interpretive Manual. The scores are available for each subtest in four age groups. To investigate interrater agreement, each NEPSY-II sample test was scored by two independent administrators. Objective data was found to have a .98 to .99 percent agreement. Some of the more subjective subtests were calculated to have a .93 to .99 percent agreement rate. In order to obtain the stability of test-retest reliability, researchers used 165 subjects to compare original and retest scores. These individuals were divided by age, gender, and ethnicity and their results were compared using the Pearson’s product-moment correlation. The results suggest high test-retest reliability overall, with a few exceptions in subtests regarding memory in which subjects performed better during their retest (Korkman, et al., 2007a).
While the NEPSY-II appears to be reliable overall, there were a few instances were validity seems compromised. Because the administration is flexible and the subtests may be given different than in the validity studies, examinees may not be represented in the reliability studies. It is expected that administrators exercise caution and complete addition research when administering the NEPSY-II to an underrepresented individual in order to ensure the best possible results (Davis & Matthews, 2010).
Presentation and Evaluation of Validity
To test the validity of the NEPSY-II, the authors and researchers opted to conduct correlation studies to measure the clinical, concurrent, construct, and content validity. Groups of varying diagnoses, including ADHD, Autism Spectrum Disorder, Hearing Impairments, and Language Disorders amongst others, were used to test the clinical administrative use. It was reported that the NEPSY-II did provide discriminatory validity amongst these groups. Concurrent validity was testing using correlations with similar cognitive tests. The results showed that the NEPSY-II had significant predictive validity in relation to these more selective cognitive tests. Research found low construct validity which is contributed to the varied domains and low subtests correlations. To ensure Content validity the original 1998 NEPSY was updated to include current neuropsychological information collected from literature and research. This lead to a more detailed range of subtests, age categories, and items within the subtests (Korkman, et al., 2007a).
The second edition of the NEPSY assessment has undergone strenuous testing and has established a wide variety of scholarly research. Most are in agreement that it is a highly reliable and valid measurement of an array of cognitive abilities that can be used in a variety of settings. Given that it can be given in three different formats (diagnostic, full, and general administrations) to individualize the...