Psychometric Characteristics of Inhibition Component of Executive Functions: Comparing Normal People with Clinical Disorders

This study was carried out with the aim of exploring the validity and reliability of the computer version of tasks for the inhibition component proportional to the Iranian population. In this investigation, three computer tasks based on Miyake and Friedman's theory of executive functions to assess inhibition were examined.

The anti-saccade task, Stroop task, and stop-signal task tests were the instruments employed in this survey. The current study is of the type of descriptive-analytical, which was conducted by quota sampling in the preliminary (pilot) stage on 100 people of four different ethnicities and languages and then on 406 normal individuals and 74 people with various clinical disorders in Kerman city (age range of 16 to 60 years). Face validity, content validity and discriminant validity were used to investigate the validity. Assessing the reliability of subscales was performed through internal consistency, test-retest, split-half correlation, and Spearman-Brown methods.

The subscales of anti-saccade, Stroop, and stop-signal tasks revealed excellent internal consistency and favorable reliability. These scales showed desirable face and content validity. The data achieved from the MANOVA analysis approach demonstrated a significant difference between the performance of normal individuals and people with different clinical disorders.

On the basis of the findings, this computer version of tasks has desirable reliability and validity to assess the inhibition component and can be employed as a valid instrument to measure the capability of inhibition in normal individuals and people with clinical disorders.