The Reliability and Criterion Validity of a Farsi Version of the State-Trait Anger Expression Inventory-2 (STAXI-2) in a Clinical Sample

This paper reports the results of a preliminary study, which examined the criterion validity and reliability of a Farsi version of the State-Trait Anger Expression Inventory (STAXI-2) amongst a clinical sample with psychological disorders. Four hundred and fifty-one patients with the mean (SD) age of 31.2 (9.7) years who met the DSM-IV-TR criteria for only one of the following disorders: anxiety disorders (n = 144), depressive disorders (n = 203), manic episode (n = 26), antisocial personality disorder and intermittent explosive disorder (n = 51) completed the Farsi version of STAXI-2. The instrument was also completed by non-clinical sample (n = 1071). The mean (SD) age of the non-clinical sample was 28 (10.1) years. In order to examine the stability of the Farsi STAXI-2 over time, the instrument was re-administered to a sub sample of 22 psychiatric patients after two weeks from the first assessment. Significant differences were found between the clinical and non-clincal samples in the proposed directions. Compared to the clinical sample, non-clinical people scored significantly lower in all scales and subscales of the Farsi STAXI-2 with the exception of Anger Control-In and Anger Control-Out. On the other hand, the non-clinical sample scored significantly higher on Anger Control-In and Anger Control-Out, compared to the clinical sample. Finally, the results of the present study revealed that the scales and subscales of the Farsi STAXI-2 are reliable, as measured in terms of internal consistency and test-retest reliability. These results provide preliminary support for the use of the Farsi STAXI-2 amongst clinical population in Iran.