Daily Fluctuations in Self-Concept Clarity and Emptiness as Predictors of Nonsuicidal Self-Injury

Cross-sectional research has shown that identity disturbance is related to nonsuicidal self-injury (NSSI). Self-concept clarity is one aspect of identity disturbance that has been associated with NSSI thoughts and behaviors. However, the majority of studies in this area have reported on their between-person relationship, limiting our understanding of their within-person association. Furthermore, self-concept clarity is closely related to the construct of emptiness, which has been linked to short-term fluctuations in NSSI. As such, it remains unknown how much of the link between self-concept clarity and NSSI is confounded by each of their correlations with emptiness. Additionally, NSSI thoughts are under-studied despite being a relevant treatment target and source of distress. This study used an ecological momentary assessment design to (a) investigate self concept-clarity as a within-person predictor of NSSI thoughts, and (b) examine the conceptual and empirical associations between self-concept clarity and emptiness. People with recurrent NSSI behaviors were recruited to participate in a 2-week EMA study that involved answering surveys four times a day. The final sample consisted of 119 participants. The hypothesis that self-concept clarity and NSSI thoughts would have a negative within-person association was supported for the contemporaneous model (i.e., when NSSI thoughts were measured at the same time as self-concept clarity). However, self-concept clarity was not found to have a prospective effect on NSSI thoughts (i.e., when NSSI thoughts were measured at the next time point, about three hours later). Meanwhile, emptiness and self-concept clarity had a significant and moderate negative within-person association, and showed independent predictive utility in accounting for NSSI thoughts on a within-person level. Future research may investigate the interplay between self-concept clarity and interpersonal factors in predicting NSSI thoughts and behaviors, and conduct qualitative studies to better understand how states like low self-concept clarity and emptiness contribute to risk of NSSI