Development and Factorial Validation of the Inventory of Deliberate Self-Harm Behaviours for Portuguese Adolescents.

Deliberate self-harm (DSH) is a public health problem that mainly affects adolescents and young adults. Evidence suggests that multiple methods are used with a self-aggressive intent. The present article focuses on the development and factorial validation of the Inventory of Deliberate Self-harm Behaviours for Portuguese adolescents. This instrument assesses the lifetime frequency of 13 DSH methods, with and without suicidal intent. Study 1 consisted of an exploratory factor analysis with a sample of 131 adolescents with a reported history of DSH. Results revealed a three-factor structure with acceptable internal consistency: High Severity DSH, Mild Severity DSH, and Substance Use DSH. After item reduction, this structure was tested in Study 2 through a confirmatory factor analysis with an independent sample of 109 adolescents also with a history of DSH. Results showed an acceptable model fit. This instrument presents a solid structure and acceptable psychometric properties, allowing its use in further research.