自傷行為に対する認知的評価尺度の作成と信頼性・妥当性の検討

[Purpose] Recent studies have focused on appraisals of self-injury as one of the factors in nonsuicidal self-injury (NSSI). However, the components of appraisal of self-injury have not been clarified and no scale for measur- ing appraisal of self-injury has been developed. The current study aims to clarify the components of appraisal of self-injury, develop an Appraisal of Self-Injury Scale (ASIS), and evaluate its reliability and validity.
[Methods] In Study 1, an interview survey was conducted with 10 university students and workers who had experi- enced NSSI, and constructs for an appraisal of self-injury related to NSSI were extracted from the interview data. The ASIS items were drafted and developed based on the constructs extracted in Study 1. In Study 2, the resulting questionnaire was administered to 376 college or university students and the reliability and validity of the developed ASIS were evaluated.
[Results] In Study 1, 11 constructs and 4 categories were extracted based on a modified grounded theory ap- proach. Based on these constructs, 50 items were drafted for ASIS. The results of exploratory factor analysis in Study 2 showed 19 items for the ASIS falling in five factors: “consideration for others,” “obsession with self-in- jury,” “limit of effect,” “usefulness of self-injury,” and “concerns of negative evaluation.”
[Discussion] The results suggest that the ASIS has adequate reliability (internal consistency and test-retest reliability) and validity (face validity, structural validity, and convergent validity). Item response theory analysis indicated that the ASIS has adequate measurement accuracy in those reporting positive appraisal of self-injury as well as usefulness, particularly for those who have previous experience of NSSI or are at risk of experiencing it. The features of each of the five factors are discussed from the aspects of previous experience of NSSI and gender differences.