2019 Volume 33 Issue 1 Pages 13-26
The concept of differentiation of self as an integrative perspective involving intrapsychic dimensions and interpersonal distance was proposed by Bowen, a transgenerational family therapist. This study sought to develop a Japanese version of the Differentiation of Self Inventory-Revised (DSI-R; Skowron ＆ Schmitt, 2003), a self-report measure of differentiation of self that includes four subscales: Emotional Reactivity (ER), I-Position (IP), Emotional Cutoff (EC), and Fusion with Others (FO).
In Study 1, the questionnaire was administered to test the validity of the subscales by examining the correlation of each with an external criterion reflecting similar constructs. In total, 193 adults participated (aged 18―29 years). Only two subscales, EC and FO, were tested in this study because the others, ER and IP, had been tested previously (Nakajima, 2011). The results showed that the EC and FO scales had sufficient validity; significant positive correlations were calculated between each subscale and its respective external criterion. The internal consistency reliabilities calculated using Chronbach's alpha were high for both subscales (.74―.79).
In Study 2, the questionnaire was administered to test the validity of all subscales, using measures of family functioning and problems of physical and mental well being as external criteria that were assumed to relate to differentiation of self. In total, 232 adults participated (aged 19 ― 58 years). All subscales were found to have sufficient validity; significant positive correlations were calculated between all subscales and family functioning, and significant negative correlations were calculated between all subscales and problems of physical and mental well being.
In conclusion, the Japanese version of the DSI-R has sufficient validity and reliability for use in statistical analyses. In research measuring the effects of interventions focused on emotional aspects of family relationships, the DSI-R is expected to contribute to integrative assessment by defining the level of differentiation at which interventions are effective: the intrapsychic or interpersonal.
