Psychometric Properties of the Inventory of Statements about Self-Injury (ISAS) in Iranian Opioid and Alcohol Abusers

Abstract

Background: Non-suicidal self-injury (NSSI) is one of the most dangerous behaviors linked to substance abuse. The Inventory of Statements About Self-Injury (ISAS) has been developed to better understanding the factors associated with the onset and maintenance of NSSI behaviors. Objective: The ISAS was translated into the Persian language to study its psychometric properties in Iranian population of opioid and alcohol abusers. Methods: This is a psychometric study investigating opioid and alcohol abusers in Iran, including those residing in addiction rehabilitation camps, prisons, hospitals, and addiction treatment clinics dispensing methadone in 2017. The sample size of this study was 470. The subjects completed the Inventory of Statements About Self-Injury, Barrat Impulsiveness Scale (BIS), and the Distress Tolerance Scale (DTS). Results: The test-retest results were estimated for two weeks using the Intra-class Correlation Coefficient (ICC). The absolute reliability was determined to be 2.62%. There was a significant correlation between convergent and divergent instruments. The results of the exploratory factor analysis on 235 individuals in the sample showed all subscales of the inventory measure a single factor in the Iranian population. The total Cronbach’s alpha coefficient for this subscale was 0.93. Also, the results of confirmatory factor analyses on the rest of the sample (235), after applying the AMOS software suggestions to improve the model, showed this inventory was a good indicator for this population (χ2 = 131.69; P < 0.001; df = 56; χ2/df = 2.35; CFI = 0.97; RMSEA = 0.76; GFI = 0.92). Conclusions: The Persian version of the Inventory of Statements About Self-Injury has high validity and reliability among the opioid and alcohol-abusing population in Iran.