(PS12-B46) Exploring the Relationship Between Diary Card Completion and Symptom Reduction in Outpatient DBT

Background

Dialectical behavior therapy (DBT) is a treatment for borderline personality disorder (BPD; Linehan, 1993). Research has shown that a significant percentage of individuals who meet criteria for BPD have also experienced trauma in their lives and that DBT treatment has helped to reduce PTSD symptoms (Steil et al., 2018). DBT uses homework such as diary cards to track clients’ application of skills throughout their course of treatment. Edwards et al., 2021 found that homework, including diary cards, in outpatient DBT were associated with reductions in several important target behaviors, including suicide and substance use; however, the relationships between these treatment components and broader symptom reduction for DBT patients is not yet well understood.

Methods

A naturalistic within-subjects design was used to examine the relationship between diary card completion  in DBT and symptom reduction across a range of mental health measures. It was hypothesized that greater diary card completion would be associated with more rapid reductions in symptoms over the course of treatment. Participants (n = 299, M age = 27.9, SD = 11.3; 65% Cisgender Women, 31% Cisgender Men, 4% Nonbinary or Transgender) were patients completing comprehensive DBT treatment at an outpatient clinic in Southern California. Measures included the PHQ-9, GAD-7, BSL-23, DERS-18, PCL-5, and FFMQ-15, and were collected at intake and every 2 months throughout treatment. Diary cards were collected daily. Mixed Linear Effects Models were used to examine the association between diary card completion and change over time in outcomes.

Results

Significant interactions between months in treatment and diary card completion rate were found for PHQ-9 (b = -.46, se = .14, p < .001), GAD-7  (b = -.32, se = .12, p = .005), and BSL-23 (b = -1.13, se = .42, p = .008), such that the higher the proportion of diary cards completed by a patient, the greater their improvement for each month of treatment. The interaction effects for the DERS-18 (b = -.49, se = .26, p = .062), PCL-5 (b = -.72, se = .40, p = .080), and FFMQ-15  (b = .30, se = .20, p = .129) were nonsignificant, though were directionally the same as the other effects.

Discussion

The primary hypothesis was partially supported: greater diary card completion was associated with more rapid improvement in symptoms of depression, anxiety, and BPD; however, this relationship was weak to nonexistent for emotion dysregulation, trauma symptoms, and trait mindfulness. These data are unable to answer the question of why diary card completion was associated with improvements in some but not all symptoms, but this would be an interesting subject for future research. This study had several limitations. First, the fact that the majority of the participants were white, women, well-educated, and able to pay for services out-of-pocket limits the generalizability and the lack of control group prevents any causal inference. Despite these limitations, this study provides insight into one of the key components of DBT, the diary card, and its relationship with symptom improvement.