The self-harm inventory: A meta-analysis of its relationship to the personality diagnostic questionnaire-4 as a measure of borderline personality disorder.

Objective: The purpose of the present study was to further examine the efficacy of the Self-Harm Inventory (SHI) as a proxy measure in diagnosing borderline personality disorder, with the comparison measure being the Personality Diagnostic Questionnaire-4 (PDQ-4).

Methods: We undertook a meta-analysis of data from our previous studies of psychiatric inpatients (N = 270) and internal medicine outpatients (N = 2587), all of whom completed both the SHI and the PDQ-4.

Results: Scores on the SHI and PDQ-4 were strongly correlated, especially after correcting for attenuation due to measurement unreliability (0.78 in the compiled inpatient psychiatry sample and 0.83 in the compiled internal medicine sample). Moreover, the SHI demonstrated statistically significantly greater reliability coefficients relative to the PDQ-4.

Conclusions: Based upon comparison with the PDQ-4, the SHI appears to be an efficacious proxy measure of borderline personality symptomatology in both psychiatric inpatient samples and primary care outpatient samples.