effectiveness of transdiagnostic treatment on anxiety sensitivity and self-differentiation in individuals with borderline personality disorder symptoms

Background and objective: borderline personality disorder (bpd) is characterized by significant challenges in emotion regulation, interpersonal relationships, and self-image, often accompanied by high anxiety sensitivity and difficulties in self-differentiation. the present study aimed to investigate the effectiveness of transdiagnostic treatment on anxiety sensitivity and self-differentiation in individuals exhibiting symptoms of bpd.materials and methods: the research employed a quasi-experimental design with pre-test, post-test, and follow-up assessments, incorporating a control group. the statistical population for this study comprised all patients diagnosed with bpd who sought psychiatric consultation in district 4 of tehran, iran, in 2024. a targeted sample of 30 participants (15 in each group) was selected based on the inclusion criteria and randomly assigned to either the experimental or control group. the research instruments included the anxiety sensitivity index and self-differentiation questionnaire. the experimental group received 10 ninety-minute sessions of transdiagnostic treatment. data analysis was performed using repeated measures analysis of variance (anova).results: results indicated that transdiagnostic treatment significantly reduced anxiety sensitivity (f=192.45, p<0.001, ηp²=0.88) and increased self-differentiation (f=201.67, p<0.001, ηp²=0.89) at the post-test stage. this positive effect persisted into the follow-up phase, demonstrating the enduring effectiveness of transdiagnostic treatment.conclusion: these findings suggest that transdiagnostic treatment can substantially alleviate anxiety sensitivity and improve self-differentiation in individuals with bpd symptoms.