English abstract
This study aimed to investigate the psychometric properties of the
Snijders Oomen Non-Verbal Intelligence Test (SON-R6-40) on students in the
sixth and ninth grades for the academic year (2023-2024). The test was
administratedto 1120 students from schools in Muscat Governorate. To verify
the characteristics, the descriptive approach was used, and statistical processing
of the data was carried out in several ways. The Construct validity, Factor
analysis, and Convergent and Discriminant validity of the test were verified,
and all results showed that the test had a good degree of validity. Verification
of the reliability of the test was also carried out using Cronbach's alpha
coefficient and the reliability equation according to modern theory, and also
according to structural equation modeling by calculating the composite
reliability coefficient, and all analyzes showed that the (SON-R6-40) test had a
high degree of reliability (≥ 0.93). The assumptions of the item response theory
(Unidimensionality, Local independence, fit of the model to the data) were also
verified on the study data.
