Psychometric Assessment of Adverse Childhood Experiences International Questionnaire (ACE-IQ) with Adults Engaging in Non-Suicidal Self-Injury

Background: The current study aimed to investigate the psychometric properties of the Adverse Childhood Experiences – International Questionnaire (ACE-IQ) with individuals engaging in non-suicidal self-injury. Numerous studies have supported the association of adverse childhood experiences with non-suicidal self-injury. However, the majority of the measures used were limited to basic forms of abuse and neglect, indicating a need for the use of a more inclusive measure, such as the ACE-IQ. The psychometric properties of the measure though have only been briefly investigated with other populations, suggesting that a more thorough examination might be beneficial before its use. Method: Two hundred eighty-four adult participants (77.5% females) with a mean age of 23.4 (SD=5.7) were recruited online via specific self-harm groups on social media platforms. Participants were asked to complete an online survey consisting of three self-report measures regarding early childhood experiences and engagement in non-suicidal self-injury. Results: The findings of this study supported ACE-IQ’s reliability (Cronbach’s alpha = 0.854), convergent validity (r= 0.85, p<0.001 with the CTQ-SF), predictive validity (R² = 0.12, p=0.001 of the SHI total score) and discriminant validity (F-value = 13.90, p<0.001). An exploration of the factor structure demonstrated a 5-factor solution (physical abuse, sexual abuse, emotional abuse, exposure to violence, family environment). Conclusions: It was concluded that ACE-IQ is a reliable and valid measure to be used for research or clinical purposes with individuals engaging in non-suicidal self-injury, although further research is needed on its factor structure. Research and clinical implications are discussed.