Objective
To empirically evaluate the diagnostic relevance of the proposed DSM-5 Criterion A frequency threshold for Non-Suicidal Self-Injury (NSSI) Disorder.
Method
Archival, de-identified self-reported clinical assessment data from 746 adolescent psychiatric patients (Mage = 14.97; 88% female; 76% white) were used. The sample was randomly split into two unique samples for data analyses. Measures included assessments of NSSI, proposed DSM-5 NSSI Disorder criteria, psychopathology, dysfunction, distress, functional impairment, and suicidality.
Results
Discriminant function analyses ran with sample A identified a significant differentiation of groups based on a frequency of NSSI at 25 or more days in the past year, Λ = .814, χ2 (54) = 72.59, p < .05, canonical R2 = .36. This cut-off was replicated in the second sample. All patients were coded into empirically derived frequency cut-off groups: High-NSSI (25+ days of NSSI), Moderate-NSSI (5–24 days of NSSI), and Low-NSSI (1–4 days of NSSI) and compared. The High-NSSI group scored higher on most NSSI features including DSM-5 proposed Criterion B and C symptoms, Depression, Psychotic symptoms, Substance Abuse, Borderline Personality Disorder features, suicidal ideation and suicide plans than the Moderate- and Low-NSSI groups, who did not differ from each other on many of the variables.
Conclusions
The currently proposed DSM-5 Criterion A frequency threshold for NSSI disorder lacks validity and clinical utility. The field needs to consider raising the frequency threshold to ensure a meaningful and valid set of diagnostic criteria are established, and to avoid over-pathologizing individuals who infrequently engage in NSSI.