Functions, lifetime frequency, and variety of methods of non-suicidal self-injury among college students.

Borderline Personality Disorder (BPD) and intrapersonal functions of non-suicidal self-injury (NSSI) have both been found to have strong relationships with NSSI. The present study examines their role in the lifetime frequency and variety of NSSI methods, taken as indicators of severity of NSSI. We hypothesized that intrapersonal functions would explain frequency and variety of NSSI beyond the effects of interpersonal functions. Further we hypothesized that intrapersonal functions would moderate the effect of BPD characteristics on frequency of NSSI. College students (n=52) who endorsed at least one lifetime act of NSSI completed self-report measures and semi-structured interviews about NSSI behaviors, frequency, variety and functions, and BPD symptoms. Results supported the hypotheses that intrapersonal functions play a role in the lifetime frequency and variety of NSSI behaviors in addition to that of interpersonal functions, but did not support the role of intrapersonal functions as a moderator. Findings are discussed in terms of relative importance of all factors involved in explaining severity of NSSI, measured as lifetime frequency and variety.