Measuring symptoms of post-traumatic stress disorder in Lebanon: psychometric validation of the Arabic version of the Impact of Event Scale-6 (IES-6)

Abstract

BACKGROUND: The Impact of Event Scale-6 (IES-6) is a reduced version of the Impact of Event Scale-Revised, and has been developed to rapidly screen for PTSD. This study aimed to psychometrically evaluate and validate a new Arabic translation of the Impact of Event Scale-6 on a sample of adults from the general population of Lebanon. METHODS: Participants (n = 601) were Arabic-speaking adults from the general population of Lebanon who completed our Arabic translation of the IES-6, along with measures of depression, anxiety and stress. To examine the factor structure of the IES-6, we conducted a Confirmatory Factor Analysis (CFA) using the data from the total sample via SPSS AMOS v.29 software. To examine gender invariance of the IES-6 scores, we conducted multi-group CFA. RESULTS: Confirmatory Factor Analysis was performed and showed that the fit of a one-factor model of the Arabic translation of the IES-6 was acceptable after we added a correlation between residuals of items 4-6 and 2-4. Total scores were found to have adequate reliability (ω = .94; α = .94). Adequate patterns of concurrent validity were also demonstrated, with IES-6 scores significantly and positively correlating with higher depression (r = .37; p < .001), anxiety (r = .43; p < .001) and stress (r = .33; p < .001). Finally, gender invariance was established at the configural, metric, and scalar levels, with females scoring significantly higher than males. CONCLUSION: Our study suggests that the Arabic translation of the IES-6 is valid and reliable for assessment of PTSD symptoms. The availability of this scale provides a standardized tool for assessing PTSD, which may enhance research efforts and facilitate the evaluation of treatment effectiveness in clinical and research settings.