The effects of once- versus twice-weekly sessions on psychotherapy outcomes in depressed patients

Background It is unclear what session frequency is most effective in cognitive-behavioural therapy (CBT) and interpersonal psychotherapy (IPT) for depression.Aims Compare the effects of once weekly and twice weekly sessions of CBT and IPT for depression.Method We conducted a multicentre randomised trial from November 2014 through December 2017. We recruited 200 adults with depression across nine specialised mental health centres in the Netherlands. This study used a 2 × 2 factorial design, randomising patients to once or twice weekly sessions of CBT or IPT over 16-24 weeks, up to a maximum of 20 sessions. Main outcome measures were depression severity, measured with the Beck Depression Inventory-II at baseline, before session 1, and 2 weeks, 1, 2, 3, 4, 5 and 6 months after start of the intervention. Intention-to-treat analyses were conducted.Results Compared with patients who received weekly sessions, patients who received twice weekly sessions showed a statistically significant decrease in depressive symptoms (estimated mean difference between weekly and twice weekly sessions at month 6: 3.85 points, difference in effect size d = 0.55), lower attrition rates (n = 16 compared with n = 32) and an increased rate of response (hazard ratio 1.48, 95% CI 1.00-2.18).Conclusions In clinical practice settings, delivery of twice weekly sessions of CBT and IPT for depression is a way to improve depression treatment outcomes

The effects of retrieval versus rehearsal of online problem-solving therapy sessions on recall, problem-solving skills and distress in distressed individuals: An experimental study

Background and objectives: Improving memory for the content of therapy sessions might increase the effects of psychological interventions. Previous studies showed that healthy individuals who took a memory test (retrieval) of studied material showed better long-term memory retention than individuals who restudied (rehearsal) the material. The aim of the current study was to find out whether we can translate these findings to a subclinical setting. Methods: Individuals with moderate levels of distress were randomized into retrieving (n = 46) or rehearsing (n = 49) four weekly sessions of online Problem-Solving Therapy (PST). Session recall, problem-solving skills and distress were measured at baseline, three days after each session and at one-week follow-up. Results: Retrieval led to overall higher recall, but this difference disappeared when controlling for the time spent on retrieval versus rehearsal. Retrieval did not lead to better problem-solving skills or less distress, compared to rehearsal. Baseline working memory performance moderated the effect of condition on recall after controlling for the time spent on retrieval versus rehearsal: the effect of retrieval compared to rehearsal on recall was larger for individuals with lower working memory performance. Limitations: The sample mostly consisted of university students with overall high working memory scores. Conclusions: This study provided the first evidence that retrieval of the content of PST sessions may lead to better session recall compared to rehearsal of the PST sessions in individuals with a low working memory score. Implications for the use of cognitive support strategies within a therapeutic setting are discussed

Direct effects of cognitive therapy skill acquisition on cognitive therapy skill use, idiosyncratic dysfunctional beliefs and emotions in distressed individuals: An experimental study

Experimental studies that manipulate treatment procedures to investigate their direct effects on treatment processes and outcomes are necessary to find out the effective elements and improve the effects of cognitive behavioral therapy (CBT) for depression. The present study randomized mildly to severely depressed participants into a procedure focused on cognitive therapy skill acquisition (CTSA; n = 27) or a control procedure focused on being exposed to theories of automatic thinking (n = 25) and investigated the direct effects on cognitive therapy (CT) skill use, credibility of idiosyncratic dysfunctional beliefs and strength of emotions. After the procedure, participants were exposed to a sad mood induction and given an assignment to test their CT skills. Participants who received the CTSA procedure used more CT skills compared to participants that received the control procedure, but there were no differences between conditions in the decrease of the credibility of idiosyncratic dysfunctional beliefs and strength of emotions. However, in participants with mild levels of depression, those who underwent the CTSA procedure showed larger decrease in the credibility of their most malleable belief (i.e. mostly automatic negative thoughts) compared to those who received the control procedure, but the significance of these findings disappeared when controlling for differences in ratings of the procedures. Future experimental studies should focus on the effects of CT skill training in the long term, the dose of the procedure and individual patient differences to find out under what circumstances the use of CT skills can lead to a reduction in dysfunctional thinking and subsequent symptoms of depression

Isolating therapeutic procedures to investigate mechanisms of change in cognitive behavioral therapy for depression

Background: Isolating a therapeutic procedure might be a powerful way to enhance our understanding of how cognitive behavior therapy (CBT) works. The present study explored new methods to isolate cognitive procedures and to study their direct impact on hypothesized underlying processes and CBT outcome. Method: The effects of a cognitive therapy skill acquisition procedure (n = 36) were compared to no procedure (n = 36) on cognitive therapy skills, dysfunctional thinking, distress, and mood in response to induced distress following a social stress test in healthy participants. Results: Participants reported more cognitive therapy skills after the procedure that focused on the acquisition of cognitive therapy skills compared to no procedure, but there were no differences in dysfunctional thinking, distress, and mood between the groups. Conclusions: By demonstrating an experimental approach to investigate mechanisms of change, including the pitfalls that come along with it, the present experiment provides a blueprint for other researchers interested in the underlying mechanisms of change in CBT for depression

The Potential Role of Learning Capacity in Cognitive Behavior Therapy for Depression: A Systematic Review of the Evidence and Future Directions for Improving Therapeutic Learning

Insight into how cognitive behavioral therapy (CBT) works is urgently needed to improve depressive outcome. First, we discuss the role of learning in CBT for depression by reviewing evidence for learning processes involved in the development and maintenance of depression. Second, we investigate the role of learning capacity as a moderator by reviewing empirical evidence for the relation between (a) CBT procedures and learning processes, (b) learning processes and CBT treatment processes, and (c) learning processes and CBT outcome. We propose that learning capacity moderates the relation between CBT procedures and change in CBT treatment processes and explains why therapeutic procedures lead to process change and long-term success in some but not all patients. Third, we identify procedures that lead to successful therapeutic learning and describe how experimental studies help to better explain causal mechanisms of change and the role of learning capacity in CBT for depression

Temporal and specific pathways of change in cognitive behavioral therapy (CBT) and interpersonal psychotherapy (IPT) for depression

Background: The present study investigated the specific and temporal role of putative mechanisms of change in cognitive-behavioral therapy (CBT) and interpersonal psychotherapy (IPT) for major depressive disorder (MDD). Method: 200 patients were randomized to CBT weekly, CBT twice weekly, IPT weekly or IPT twice weekly. Outcome and putative mechanisms of change (i.e., dysfunctional thinking, behavioral activation, CBT skills, IPT skills, therapeutic alliance, compliance, motivation) were measured multiple times up to six months after the start of treatment. Latent change score models were used to investigate temporal relations and test mediation. Explorative analyses tested whether baseline working memory moderated the effect of mechanism change on outcome change. Results: CBT skills and dysfunctional thinking mediated the relation between treatment modality and changes in depression. In both treatments, IPT skills and behavioral activation were related to subsequent change in depression while a decrease in depression led to subsequent improvement in therapeutic alliance and a decrease in autonomous motivation. Change in compliance was unrelated to change in depression. Baseline working memory was related to therapy skill improvement. Conclusion: CBT skill improvement seems a specific mechanism of change leading to subsequent decrease in depression in CBT. Changes in IPT skills acted as a non-specific mechanism, subsequently reducing depression regardless of treatment modality. The specific role of cognitive change and behavioral activation remains unclear. Future studies should investigate the specificity and direction of the potential mechanisms of change throughout the course of therapy and investigate whether these mechanistic pathways differ between individuals

Mechanistic pathways of change in twice weekly versus once weekly sessions of psychotherapy for depression

Background: Recently, we showed that twice weekly sessions of cognitive-behavioral therapy (CBT) and interpersonal psychotherapy (IPT) for depression lead to better and faster treatment outcomes compared to once weekly sessions (Bruijniks et al., 2020). The present study investigated which pathways of change may account for the effects of different session frequencies. Method: The sample consisted of 200 patients who were randomized to CBT weekly, CBT twice weekly, IPT weekly, or IPT twice weekly. Outcome and therapy processes were measured at baseline, two weeks and monthly up to month 6 after the start of treatment. Latent change score models investigated temporal relations between change in therapy processes and change in depression and tested whether change in the therapy processes mediated the effect of session frequency on change in depression. Results: IPT skills mediated the relation between session frequency and change in depression. A decrease in depression was related to subsequent improvement in CBT skills and subsequent decrease in motivation for therapy. Conclusion: The development of IPT skills may explain why a twice weekly higher session frequency is more effective in reducing depression compared to a once-weekly session frequency. Future studies should disentangle the causal effects of therapy process change throughout the course of therapy

Individual differences in response to once versus twice weekly sessions of CBT and IPT for depression

OBJECTIVE: The Personalized Advantage Index (PAI) is a method to guide treatment selection by investigating which of two or more treatments is optimal for a given individual. Recently, it was shown that, on average, twice-weekly sessions of psychotherapy for depression lead to better outcomes compared to once-weekly sessions. The present study applied the PAI method to assess if subgroups of patients may have a differential response to psychotherapy frequency. METHOD: Data came from a clinical trial (n = 200) randomizing depressed patients into different session frequencies: weekly sessions versus twice-weekly sessions. Machine-learning techniques were used to select pretreatment variables and develop a multivariable prediction model that calculated each patient's PAI. Differences in observed depression post-treatment scores (Beck Depression Inventory-II [BDI-II]) were tested between patients that received their PAI-indicated versus non-indicated session frequency. Between-group effect sizes (Cohen's d) were reported. RESULTS: We identified prognostic indicators generally associated with lower post-treatment BDI-II regardless of treatment assignment. In addition, we identified specific demographic and psychometric features associated with differential response to weekly- versus twice-weekly therapy sessions. Observed post-treatment BDI-II scores were significantly different between individuals receiving the PAI-indicated versus non-indicated session frequency (d = .37). CONCLUSIONS: Although a higher session frequency is more effective on average, different session frequencies seem beneficial for different patients. Future studies should externally validate these findings before they can be generalized to other settings. (PsycInfo Database Record (c) 2022 APA, all rights reserved)

Cross-trial prediction in psychotherapy:External validation of the Personalized Advantage Index using machine learning in two Dutch randomized trials comparing CBT versus IPT for depression

Objective: Optimizing treatment selection may improve treatment outcomes in depression. A promising approach is the Personalized Advantage Index (PAI), which predicts the optimal treatment for a given individual. To determine the generalizability of the PAI, models needs to be externally validated, which has rarely been done. Method: PAI models were developed within each of two independent trials, with substantial between-study differences, that both compared CBT and IPT for depression (STEPd: n = 151 and FreqMech: n = 200). Subsequently, both PAI models were tested in the other dataset. Results: In the STEPd study, post-treatment depression was significantly different between individuals assigned to their PAI-indicated treatment versus those assigned to their non-indicated treatment (d =.57). In the FreqMech study, post-treatment depression was not significantly different between patients receiving their indicated treatment versus those receiving their non-indicated treatment (d =.20). Cross-trial predictions indicated that post-treatment depression was not significantly different between those receiving their indicated treatment and those receiving their non-indicated treatment (d =.16 and d =.27). Sensitivity analyses indicated that cross-trial prediction based on only overlapping variables didn’t improve the results. Conclusion: External validation of the PAI has modest results and emphasizes between-study differences and many other challenges