Non-suicidal self-injury (NSSI) functions, scarring, and medical lethality may be more important to assess than commonly regarded NSSI severity indices when ascertaining suicide risk, a recent study found. Individuals with a history of NSSI are at alarmingly high risk for suicidal ideation (SI), planning (SP), and attempts (SA). However, previous studies have not examined the wide range of NSSI characteristics simultaneously when determining which NSSI features are most salient to suicide risk. The current study utilized 3 exploratory data mining techniques (elastic net regression, decision trees, random forests) to address these gaps in the literature. Undergraduates with a history of NSSI (n=359) were administered measures assessing demographic variables, depression, and 58 NSSI characteristics (eg, methods, frequency, functions, locations, scarring) as well as current SI, current SP, and SA history. Researchers found:

• Depressive symptoms and the anti-suicide function of NSSI were the most important features of NSSI for predicting SI and SP.
• The most important features in predicting SA were the anti-suicide function of NSSI, NSSI-related medical treatment, and scarring.