suddengains: An R package to identify sudden gains in longitudinal data

Sudden gains in internet cognitive therapy for social anxiety disorder in routine clinical practice

Background

Sudden gains are large symptom improvements between consecutive therapy sessions. They have been shown to occur in randomised controlled trials of internet-delivered psychological interventions, but little is known about their occurrence when such treatments are delivered in routine clinical practice.

Objective

This study examined the occurrence of sudden gains in a therapist-guided internet-delivered Cognitive Therapy intervention for social anxiety disorder (iCT-SAD) delivered in the UK NHS talking therapies for anxiety and depression (formerly known as IAPT services). It aimed to assess whether sudden gains were associated with better therapy outcomes, and examine changes in process variables around the period of sudden gains.

Methods

The study examined sudden gains based on the Liebowitz Social Anxiety Scale. Of 193 treated patients, 146 provided sufficient data to permit analysis. Linear mixed effects models were used to examine the impact of sudden gains on clinical outcomes, and examine changes in negative social cognitions, self-focused attention, and depressed mood.

Results

Seventy sudden gains were found among 57 participants. The occurrence rate of sudden gains was 39 %. Individuals who experienced sudden gains had a larger reduction in social anxiety symptoms at end of intervention and at three-month follow-up. There was evidence of a reduction in the frequency of negative social cognitions prior to the gain, whereas changes in self-focused attention occurred simultaneously with the gain. Depressed mood did not show significant changes over these timepoints.

Conclusions

Approximately 2 in 5 patients experienced a sudden gain whilst accessing the iCT-SAD intervention in routine practice. They were associated with better clinical outcomes following treatment compared to those who did not experience a sudden gain.

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.

Intraindividual variability and emotional change as predictors of sudden gains in imagery rescripting and EMDR for PTSD in adult survivors of childhood abuse

Sudden gains, defined as large and stable improvements in symptom severity during psychological treatment, have consistently been found to be associated with better outcomes across treatments and diagnoses. Yet, insights on coherent predictors of sudden gains and on emotional changes around sudden gains in post-traumatic stress disorder (PTSD) are lacking. We aimed at replicating a measure of intraindividual variability as a predictor for sudden gains and testing its independence from change during treatment. Furthermore, we expected changes in emotions of guilt, shame and disgust prior to sudden gains to predict sudden gains. Data from a pre-registered randomized controlled trial (RCT) of eye-movement desensitization and reprocessing (emdr) and Imagery Rescripting (ImRs) for PTSD in 155 adult survivors of childhood abuse were used. Intraindividual variability of PTSD symptoms in both treatments did not predict sudden gains status and was not independent of change during treatment. In the EMDR condition, levels of shame during treatment predicted sudden gains and shame decreased shortly before a sudden gain in both treatments. Reductions in all emotions during sudden gains were significantly higher for participants with sudden gains than for comparable intervals in non-sudden gainers. Our findings do not support the predictive validity of intraindividual variability for sudden gains. The decrease of guilt, shame and disgust during sudden gains warrants further research on their role as a mechanism of treatment change for PTSD.

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.

Within-day sudden gains and generalized anxiety disorder psychotherapy outcome

According to dynamic systems theory, initial symptom instability is necessary for long-term stable change to occur from psychotherapy. Such instability may be assessed using within-day sudden gains (SGs), sudden losses (SLs), and reversals. The present study examined these symptom change patterns and their association with treatment outcome using intensive diary assessment across three psychotherapies for generalized anxiety disorder (GAD). In a secondary analysis of Borkovec and Costello (1993), 59 clients diagnosed with GAD were randomly assigned to applied relaxation (AR; n = 21), cognitive behavioral therapy (CBT; n = 20), or nondirective (ND) therapy (n = 18). Clients completed thrice daily anxiety ratings while receiving psychotherapy. The occurrence of SGs, SLs, and reversals assessed for each individual was calculated using changes between each assessment. We examined the association between occurrence of SGs, SLs, and reversals and symptom change from pretreatment to posttreatment, and 6-month, and 1-year follow-up. Clients in ND (61.1%) were more likely to experience SGs than clients in CBT (20.0%) or AR (38.0%). 92.9% of SGs were followed by a reversal. Experiencing SGs was associated with less symptom change from pretreatment to follow-up in ND and not associated with outcome in CBT or AR. SLs and reversals were not associated with outcome. When measured at a within-day level, SGs are very likely to be reversed and may be associated with poorer long-term outcome in ND. Within-day SGs may have a fundamentally different meaning than session-to-session SGs. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

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.

Sudden gains and large intersession improvements in internet-based psychodynamic treatment (IPDT) for depressed adolescents

Objective: Sudden gains (SGs) have often been found associated with better treatment outcome across different psychiatric disorders. However, no studies have evaluated SGs in internet-based treatment targeting adolescent depression. Method: The sample consisted of 66 adolescents diagnosed with major depressive disorder, attending psychodynamic internet-based treatment. Effects of SGs were evaluated at posttreatment and 6-month follow-up. We also evaluated effects of large intersession improvements (LIIs; sudden and relatively large gains, between sessions, without the stability criterion). Effects of SGs and LIIs early in treatment were also investigated. Results: A total of 17 patients (25.75%) experienced an SG. The effect of having an SG or early SG was non-significant after treatment (d = 0.48) and at follow-up (d = 0.66). However, having an LII was related to better outcome after treatment (d = 0.97) and at follow-up (d = 0.76). Early LIIs were associated with significantly better results at end of treatment (d = 0.72). Conclusions: The original criteria of SGs might be overly conservative and thus miss important improvements in depression. Relatively large intersession gains, regardless of stability, seem to be predictive of outcome.

Cognitive processes associated with sudden gains in cognitive therapy for posttraumatic stress disorder in routine care

Objective: Although most studies investigating sudden gains in treatments for posttraumatic stress disorder (PTSD) report a positive association between sudden gains and outcomes at the end of treatment, less is known about sudden gains in routine clinical care and the processes involved in their occurrence. This study investigated changes in cognitive factors (negative appraisals, trauma memory characteristics) before, during, and after sudden gains in PTSD symptom severity. Method: Two samples (N₁ = 248, N₂ = 234) of patients who received trauma-focused cognitive therapy for PTSD in routine clinical care were analyzed. Mahalanobis distance matching, including the propensity score, was used to compare patients with sudden gains and similar patients without sudden gains. Estimates from both samples were meta-analyzed to obtain pooled effects. Results: Patients with sudden gains (n₁ = 76, n₂ = 87) reported better treatment outcomes in PTSD symptom severity, depression, and anxiety at the end of therapy and follow-up than those without sudden gains. No baseline predictors of sudden gains could be reliably identified. During sudden gains, those with sudden gains had greater changes in both cognitive factors than matched patients. Meta-analyses of the two samples showed that negative appraisals had already decreased in the session prior to sudden gains compared with matched patients. Conclusions: The pooled estimates suggest that changes in negative trauma-related appraisals precede sudden gains in PTSD symptoms. The results suggest that interventions that promote change in appraisals may also facilitate sudden gains in therapy.

This study highlights that a substantial subgroup of patients with PTSD showed concurrent large improvements in PTSD, appraisals, and memory features from one treatment session to the next. Sudden gains were also preceded by greater changes in appraisals than sessions that did not include sudden gains. This supports interventions that target the identification and modification of negative appraisals in PTSD, which, if successful, can result in sudden symptom improvements that are associated with better treatment outcomes.