Sudden gains in routine clinical care: application of a permutation test for trauma-focused cognitive behavioural therapy

Background: Sudden gains, defined as large and stable improvements of psychopathological symptoms, are a ubiquitous phenomenon in psychotherapy. They have been shown to occur across several clinical contexts and to be associated with better short-term and long-term treatment outcome. However, the approach of sudden gains has been criticized for its tautological character: sudden gains are included in the computation of treatment outcomes, ultimately resulting in a circular conclusion. Furthermore, some authors criticize sudden gains as merely being random fluctuations.Objective: Use of efficient methods to evaluate whether the amount of sudden gains in a given sample lies above chance level.Method: We used permutation tests in a sample of 85 patients with posttraumatic stress disorder (PTSD) treated with trauma-focused cognitive behaviour therapy in routine clinical care. Scores of self-reported PTSD symptom severity were permuted 10.000 times within sessions and between participants to receive a random distribution.Results: Altogether, 18 participants showed a total of 24 sudden gains within the first 20 sessions. The permutation test yielded that the frequency of sudden gains was not beyond chance level. No significant predictors of sudden gains were identified and sudden gains in general were not predictive of treatment outcome. However, subjects with early sudden gains had a significantly lower symptom severity after treatment.Conclusions: Our data suggest that a significant proportion of sudden gains are due to chance. Further research is needed on the differential effects of early and late sudden gains.

Using machine learning to predict sudden gains in intensive treatment for PTSD

Sudden gains have been found in PTSD treatment across samples and treatment modality. Sudden gains have consistently predicted better treatment response, illustrating clear clinical implications, though attempts to identify predictors of sudden gains have produced inconsistent findings. To date, sudden gains have not been examined in intensive PTSD treatment programs (ITPs). This study explored the occurrence of sudden gains in a 3-week and 2-week ITP (n = 465 and n = 235), evaluated the effect of sudden gains on post-treatment and follow-up PTSD severity while controlling for overall change, and used three machine learning algorithms to assess our ability to predict sudden gains. We found 31% and 19% of our respective samples experienced a sudden gain during the ITP. In both ITPs, sudden gain status predicted greater PTSD symptom improvement at post-treatment (t2 W=-8.57, t3 W=-14.86, p < .001) and at 3-month follow-up (t2 W=-3.82, t3 W=-5.32, p < .001). However, the effect for follow-up was no longer significant after controlling for total symptom reduction across the ITP (t2 W=-1.59, t3 W=-0.32, p > .05). Our ability to predict sudden gains was poor (AUC <.7) across all three machine learning algorithms. These findings demonstrate that sudden gains can be detected in intensive treatment for PTSD, though their implications for treatment outcomes may be limited. Moreover, despite the use of three machine-learning methods across two fairly large clinical samples, we were still unable to identify variables that accurately predict whether an individual will experience a sudden gain during treatment. Implications for clinical application of these findings and for future studies are discussed.

Sudden gains in face-to-face and internet-based cognitive therapy for social anxiety disorder

Sudden gains are large and stable decreases in clinical symptoms between consecutive therapy sessions. This work examined the frequency and possible determinants of sudden gains in Cognitive Therapy for Social Anxiety Disorder, comparing face-to-face (CT) and internet-based (iCT) formats of treatment delivery. Data from 99 participants from a randomised controlled trial were analysed. The frequency of sudden gains was high: 64% and 51% of participants experienced a sudden gain in CT and iCT respectively. Having a sudden gain was associated with lower social anxiety symptoms at posttreatment and follow-up. There was evidence of reductions in negative social cognitions and self-focused attention immediately prior to the sudden gain, contrasting with no prior reductions in depression symptoms. Ratings of session videotapes in CT showed that clients' statements indicated greater generalised learning in sessions immediately prior to gains, compared to control sessions. This may suggest a role for generalised learning in facilitating these large symptom reductions. There were no significant differences in results between the CT and iCT treatment formats, suggesting that the therapy content appears to play a more important role in determining participants' large symptom improvements than the medium of treatment delivery.

Using machine-learning to predict sudden gains in treatment for major depressive disorder

OBJECTIVE

Sudden gains during psychotherapy have been found to consistently predict treatment outcome but evidence on predictors of sudden gains has been equivocal. To address this gap, the present study utilized three machine learning algorithms to predict sudden gains during treatment for major depressive disorder.

METHOD

We examined predictors of sudden gains in two large samples of individuals receiving treatment in a partial hospital setting (n = 726 and n = 788; total N = 1514). Predictors included age, gender, marital status, education, employment status, previous hospitalization, comorbid diagnoses, and pretreatment measures of depressive and generalized anxiety symptoms. We used three machine learning models: a Random Forest model, a Random Forest model with an adaptive boosting meta-algorithm, and a Support Vector Machine model.

RESULTS

In both samples, sudden gains were identified and found to significantly predict outcome. However, none of the machine learning algorithms was able to identify robust predictors of sudden gains. Thus, even though some models achieved fair prediction of sudden gains in the training subset, prediction in the test subset was poor.

CONCLUSIONS

Despite the use of a large sample and three machine-learning models, we were unable to identify robust demographic and pretreatment clinical predictors of sudden gains. Implications for clinical decision making and future studies are discussed.

A Revised Theory of Sudden Gains in Psychological Treatments

Sudden gains were first defined and quantified by Tang and DeRubeis (1999) and were found to predict treatment outcome in cognitive therapy for depression. Since that seminal paper, over 100 examinations of sudden gains have been published and sudden gains have been found to be ubiquitous in psychological treatments and to consistently predict better treatment outcomes across a multitude of disorders and contexts (see Shalom & Aderka, 2020 for a review). The research on sudden gains has seen considerable growth over the past 20 years. However, the theory behind sudden gains (which addresses processes leading to sudden gains, and processes resulting from sudden gains) has never been revised. Based on the empirical research which has accrued over the last 20 years, we present an empirically-based revision of the theory of sudden gains. The revised theory addresses both predictors of sudden gains and processes that may lead to sudden gains, as well as the consequences of sudden gains and the processes by which sudden gains can affect outcome. We also present a number of hypotheses that can be derived from the theory as well as the status of empirical evidence supporting these hypotheses. Research and clinical implications are discussed.

A meta-analysis of sudden gains in psychotherapy: Outcome and moderators

Sudden gains have been shown to be a common phenomenon and an important predictor of outcome in psychotherapy (Tang & DeRubeis, 1999). The present meta-analysis examined the growing literature on sudden gains in psychotherapy, their effects on outcome, and moderators of these effects. We searched PsycINFO, PubMed, ProQuest Dissertations & Theses, Scholar and Web of Science databases for articles between January 1st 1999 and May 31st 2019 and included 50 studies (n = 6355) in the meta-analysis. Sudden gains were found to significantly predict outcome at post-treatment (g = 0.68) and follow up (g = 0.61) above and beyond treatments, disorders and settings. Studies using Tang and DeRubies's (1999) criteria for identification of sudden gains had smaller effect sizes compared to studies using altered criteria. Pretreatment severity levels did not significantly predict the effects of sudden gains and neither did treatment setting (randomized controlled trials vs. naturalistic settings). Finally, number of sessions and sudden gains' reversal rates were both negatively associated with the effect sizes of sudden gains. These findings suggest that sudden gains are a ubiquitous phenomenon in psychotherapy but their effects may be moderated by a number of factors. Research and clinical implications are discussed.

Sudden gains in cognitive behavioral therapy among children and adolescents with obsessive compulsive disorder

BACKGROUND AND OBJECTIVES

This study examined the occurrence of sudden gains (or reversal of gains) among children with obsessive-compulsive disorder (OCD) during the course of cognitive-behavioral therapy (CBT), as well as the association of sudden gains with treatment response, treatment group, and pre-treatment clinical characteristics.

METHODS

The sample consisted of 136 youth (ages 7-17) with a primary diagnosis of OCD who were randomized in a double-blinded fashion to 10 sessions of CBT with augmentation of either d-cycloserine or placebo. Sudden gain status was determined based on clinician-rated obsessive-compulsive symptom severity, which was collected on 9 occasions across the study period.

RESULTS

42.6% of youth experienced at least one sudden gain, which tended to occur either after starting exposure and response prevention or towards the end of treatment. After applying the Benjamini-Hochberg procedure for multiple comparisons, there were no significant pre-treatment predictors of sudden gains and only reduced insight predicted the reversal of gains. Individuals with at least one sudden gain had improved overall treatment outcomes, measured both by reduction in OCD symptom severity, and by global illness severity.

LIMITATIONS

Several clinical constructs were not examined. Symptomatology was not assessed at every treatment session. Differences in those who achieved sudden gains and those who did not may be obscured. There is the possibility that a sudden gain reflected a scoring error generated by an optimistic or inaccurate report. Finally, a relatively homogenous sample may limit the generalizability of results.

CONCLUSIONS

The course of CBT for pediatric OCD is variable with many children experiencing sudden gains, but a sizable percentage experience a reversal of gains which was related to reduced insight. Sudden gains tended to occur after starting exposure and response prevention and towards the end of treatment.

TRIALSREGISTRATION

ClinicaltrialsgovRegistry:NCT00864123. https://www.clinicaltrials.gov/ct2/show/NCT00864123.

Do sudden gains predict treatment outcome in social anxiety disorder? Findings from two randomized controlled trials

OBJECTIVE

Sudden gains (SGs) have been found to occur during randomized controlled trials (RCTs) for social anxiety disorder (SAD). Evidence is mixed whether SGs relate to treatment outcome in SAD. We examined SGs in two RCTs for SAD.

METHOD

Study 1 (N = 68) examined SGs in individual cognitive-behavioral therapy (CBT), and Study 2 (N = 100) compared SGs in group CBT and Mindfulness-Based Stress Reduction (MBSR). Weekly ratings of social anxiety were used to calculate SGs. The Liebowitz Social Anxiety Scale-Self-Report and the Social Interaction Anxiety Scale were completed at pretreatment, posttreatment, and follow-up to assess outcome.

RESULTS

In Study 1, 17.6% of participants experienced a SG. Participants with SGs started and ended treatment with lower social anxiety. SGs were not associated with greater decreases in social anxiety from pre-to posttreatment or 12-month follow-up. In Study 2, SGs occurred in 27% of participants and at comparable rates in MBSR and group CBT. SGs were not associated with changes in social anxiety during treatment in either condition.

CONCLUSION

SGs occurred during treatment for SAD. In both RCTs, participants improved regardless of experiencing a SG, suggesting that SGs are not predictive of greater improvement during treatment for SAD.

Predictors and consequences of sudden gains in transdiagnostic cognitive-behavioural therapy for anxiety disorders

Sudden gains-substantial stable symptom improvements between consecutive therapy sessions-are a common phenomenon. As condensed points of change, examination of sudden gains can provide insight into mechanisms of therapeutic change. This study investigated the association between sudden gains and cognitive change, therapeutic alliance, and/or client engagement in transdiagnostic group cognitive-behavioural therapy for anxiety disorders. Of 58 treatment initiators, 21% (n = 12) exhibited a sudden gain. Consistent with previous research, sudden gainers demonstrated significantly greater pre- to post-treatment symptom improvement than non-sudden gainers. Observational coding of therapy sessions found that sudden gains were associated with elevated levels of cognitive change and client engagement in the pre-gain session, and elevated levels of cognitive change and therapeutic alliance in the post-gain session. However, these results varied by use of within- and between-subject control comparisons, highlighting the value using a dual control methodology. In context of previous research, the results on cognitive change replicate previous findings in depressive populations, and clarify mixed findings in anxiety populations. The results on therapeutic alliance replicate previous findings for the first time in an anxiety sample, although the between-subject control comparisons revealed complexity previously undetected. This study was also the first to investigate and thus establish the relation between client engagement and sudden gains.

How to customize a bona fide psychotherapy for generalized anxiety disorder? A two-arms, patient blinded, ABAB crossed-therapist randomized clinical implementation trial design [IMPLEMENT 2.0]

BACKGROUND

Bona fide psychotherapy approaches are effective treatments for generalized anxiety disorder (GAD) compared to no-treatment conditions. Treatment manuals and protocols allow a relatively high degree of freedom for the way therapists implement these overall treatment packages and there is a systematic lack of knowledge on how therapists should customize these treatments. The present study experimentally examines two implementation strategies of customizing a bona fide psychotherapy approach based on a 16 session time-limited cognitive-behavioral therapy (CBT) protocol and their relation to the post-session and ultimate treatment outcomes.

METHODS

This trial contrasts two different implementation strategies of how to customize the in-session structure of a manual-based CBT-protocol for GAD. The patients will be randomly assigned to two implementation conditions: (1) a systematic focus on subtle changes lasting from 7 to 20 min at the check-in phase of every psychotherapy session and (2) a state-of-the-art (SOTA) check-in phase lasting several minutes mainly focused on the session goals. Potential therapist effects will be examined based on an ABAB crossed-therapist design. Treatment outcomes will be assessed at the following times: post-session outcomes, treatment outcome at post assessment and 6- as well as 12-month follow-up.

DISCUSSION

The proposed randomized clinical implementation trial addresses the clinically relevant question of how to customize a bona fide psychotherapy protocol experimentally contrasting two implementation strategies. Through the development and testing of the proposed implementation design, this trial has the potential to inform therapists about efficacious implementation strategies of how to customize a manual-based treatment protocol in respect to the timing of the in-session structure.

TRIAL REGISTRATION

This trial was registered at ClinicalTrials.gov ( NCT03079336 ) at March 14, 2017.

Moderators of sudden gains after sessions addressing emotion regulation among women in treatment for alcohol use

Sudden gains (SGs) are defined as abrupt and significant improvements in mental health symptoms that occur between two psychotherapy sessions. Preliminary evidence suggests that SGs may be an important pattern of symptom reduction in the treatment of alcohol use disorder (AUD) (i.e., a steep between-session reduction in drinking or alcohol craving frequency or intensity) (Drapkin, Epstein, McCrady, & Eddie, 2015). The current study examined SGs within two randomized clinical trials (RCTs) testing female-specific cognitive behavior therapy (CBT) protocol for AUD (n=146). We tested a priori hypotheses about whether women's baseline depression, anxiety, and confidence to be abstinent while in a negative emotional state would predict attainment of SGs after attending sessions that addressed depression, anxiety, and emotion regulation (i.e., sessions five and six of the 12-session protocol). Data were collected at baseline, within treatment, and 15months after baseline. Results showed that women with high levels of depression and/or anxiety and low confidence to be abstinent in a negative emotional state at baseline were more likely to experience a SG (steep decrease in drinking) after sessions five and six (p=0.02). Further, among women with high levels of depression and/or anxiety at baseline, those who experienced both a SG in drinking after session five/six and had higher confidence to remain abstinent in a negative emotional state at the end of treatment reported lower drinking frequency at 9- but not 15-month follow-up [95% CI=(-2.65, -0.86)]. Findings support the value of providing interventions targeting mood and emotion regulation in AUD treatment for women.

Shape of change in internet based behavioral activation treatment for depression

Shape of change, sudden gains and depression spikes were examined in an online 12-session Behavioral Activation (BA) treatment for depression. Client and therapist factors related to sudden gains were examined to investigate processes associated with outcome.

METHODS

Participants were postpartum Women with Major Depressive Disorder (n=42) who received online BA supported in 30-minute telephone sessions by a mental health worker. Depression symptoms were assessed at each session and number of sessions completed were recorded by the online program. Therapist records were rated for client stressful life event and therapist concrete focus. A quadratic pattern provided the best fit with the data; a cubic pattern was a poor fit. Sudden gains, but not depression spikes, predicted lower depression scores at 17-week outcome. Women who had higher baseline social functioning, did not experience a stressful life event during therapy, and completed more online modules, but not more telephone sessions, were more likely to have a sudden gain. A concrete therapist focus was associated with sudden gains. These results extend research on trajectories of change and sudden gains to an online BA treatment and to postpartum depression, and suggest important client and therapist factors associated with sudden gains.

Sudden gains in exposure therapy for obsessive-compulsive disorder

Prior research in the treatment of depression and anxiety has demonstrated that a sudden reduction in symptoms between two consecutive sessions (sudden gain) is related to lower post-treatment symptom severity (e.g. Hofmann, Schulz, Meuret, Moscovitch, & Suvak, 2006; Tang & DeRubeis, 1999). However, only one study has examined sudden gains in the treatment of obsessive compulsive disorder (OCD). In that study, one-third of the patients with OCD experienced a sudden gain (Aderka et al., 2012). Further, patients who had a sudden gain had lower clinician-rated OCD symptom severity post-treatment (Aderka et al., 2012). In replication, the current study examined the frequency, characteristics, and clinical impact of sudden gains in 27 OCD patients during exposure and response prevention (ERP) therapy. Fifty two percent of patients experienced a sudden gain. The mean magnitude of a sudden gain represented, on average, 61.4% of total symptom reduction. Following treatment, individuals who had experienced a sudden gain were rated as less severe on the clinical global impression scale, but they did not experience a greater reduction in OCD symptoms (pre-to post-treatment) than those without a sudden gain. None of the pre-treatment characteristics tested were found to significantly predict whether a patient would have a sudden gain. Additional research examining predictors of, and patterns of, change in OCD symptoms is warranted.

Sudden gains in internet-based cognitive behaviour therapy for severe health anxiety

OBJECTIVE

A sudden gain is defined as a large and stable individual improvement occurring between two consecutive treatment sessions. Sudden gains have been shown to predict better long-term improvement in several treatment studies, including cognitive behavioural therapy for depression and anxiety disorders, but have not been studied in the treatment of health anxiety or any form of internet-based cognitive behavioural therapy. The aim of this study was to investigate the role of sudden gains in internet-based cognitive behavioural therapy for severe health anxiety.

METHOD

We examined the occurrence and significance of sudden gains in measures of health anxiety in 81 participants receiving internet-based cognitive behavioural therapy. We compared patients with sudden gains, patients without sudden gains, and patients with gradual gains.

RESULTS

Thirteen participants (16%) experienced one sudden gain in health anxiety with individual sudden gains distributed across the treatment. As expected, patients with a sudden gain showed larger improvements than patients without a sudden gain at post-treatment (d = 1.04) and at one-year follow-up (d = 0.91) on measures of health anxiety.

CONCLUSIONS

Consistent with previous studies, sudden gains in internet-based cognitive behavioural therapy are associated with significantly larger and stable treatment effects up to one-year follow-up.

Sudden Gains During Patient-Directed Expressive Writing Treatment Predicts Depression Reduction in Women with History of Childhood Sexual Abuse: Results from a Randomized Clinical Trial

Sudden gains are large reductions in symptoms measured in a single between-session interval and are positively associated with long-term treatment outcomes. To date, sudden gains have mostly been observed in therapist-directed psychotherapies. There are currently mixed findings surrounding the mechanisms underlying sudden gains, with some support for a cognitive mechanism and some support for therapist characteristics such as the therapeutic alliance. In this study of 77 female survivors of childhood sexual abuse, sudden gains in trauma symptoms were found in a randomized clinical trial of a patient-directed expressive writing intervention. Women in the active treatment condition (who wrote about their beliefs related to sexuality or trauma) exhibiting sudden gains in trauma symptoms showed larger improvements in depression than those in the control condition (who merely wrote about their daily needs). The extension of sudden gains from psychotherapy to a client-directed treatment refines our understanding of the mechanisms underlying these gains, and supports the hypothesis that cognitive change is a likely mechanism underlying sudden gains.