Development and initial validation of scales to assess Decisional Balance (NSSI-DB), Processes of Change (NSSI-POC), and Self-Efficacy (NSSI-SE) in a population of young adults engaging in nonsuicidal self-injury.

Tools for assessing an individual's readiness to change nonsuicidal self-injury (NSSI) are limited. The Transtheoretical model of change (TTM) has been useful in predicting behavior change and guiding interventions for a variety of health behaviors including eating disorders, substance use disorders, and exercise. The aim of the current study was to examine the validity of test score interpretations from 3 newly developed measures to assess NSSI behavior change. Following in-depth interviews, modifications to existing TTM scales were made and tested with a set of web-based measures delivered to people who self-injure. This resulted in 11 new scales that reflect 3 domains associated with behavior change: NSSI-Decisional Balance (NSSI-DB), NSSI-Processes of Change (NSSI-POC), and NSSI-Self-Efficacy (NSSI-SE). Overall, results provide support for the reliability of test scores and validity of test scores interpretations. Implications for research, clinical use, and next steps are discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).