Clarifying the Definition of Nonsuicidal Self-Injury

Background: Challenges and inconsistencies in defining nonsuicidal self-injury (NSSI) have persisted for decades, which significantly impact NSSI conceptualization and assessment in clinical and research settings and impede the field's progress. Aims: The present study aimed to solicit opinions from individuals with NSSI expertise so as to improve the operational definition and conceptualization of NSSI. Method: We asked researchers, clinicians, and graduate students with varying NSSI expertise to provide opinions on six NSSI definitional components (e.g., whether pain should be a required outcome), as well as to review 118 behaviors and indicate whether each is NSSI. Results: Responses (N = 159) revealed good agreement on specific NSSI definitional aspects and the classification of oft-cited NSSI behaviors. However, findings also demonstrated potential discrepancies in how clinicians and researchers define NSSI when compared with specific behaviors that might be classified as NSSI. Limitations: The opinions of the study's sample may not reflect the wider NSSI field. Conclusion: Findings suggest that there is an increased need for a clear and consistent definition of NSSI and specific NSSI behaviors. There is also a need to develop new assessment measures that capture the range of NSSI behaviors that received good-to-excellent agreement among self-injury experts.