Studies of psychological interventions for the prevention of depression have found significant effects in the short-term, but the long-term efficacy has yet to be determined. This study evaluated the 8-year effect of a randomized controlled trial for indicated prevention of depression in female caregivers.

A total of 173 non-professional female caregivers with subclinical depressive symptoms not meeting criteria for a major depressive episode (MDE) were randomized to either a brief problem-solving intervention (n = 89) or usual-care control group (n = 84). Blinded evaluators conducted an assessment at the 8-year follow-up. The primary outcome was Depression Status, defined by diagnoses of MDE since the 1-year follow-up using the Structured Clinical Interview for the Disorders of the DSM-5. The secondary outcome was current Depressive Symptom Severity. Regression analyses were conducted to evaluate the effect of the intervention on the outcomes.

There were no significant differences in the Depression Status between the problem-solving (30.3%) and control groups (26.2%) (adjusted OR 1.25, 95% CI −0.58 to 2.69). Depressive Symptom Severity, however, was significantly lower in the problem-solving group compared to the control group at this follow-up, amounting to a small effect size of Cohen's d = 0.39 (adjusted B = −3.32, p = 0.018).

This is the first study to assess such a long-term follow-up of intervention of indicated prevention of depression. Results seem to indicate that the protective effect of the intervention became smaller over time during follow-up. Future research should replicate these results.

The Hamilton Depression Rating Scale (HAMD) and the Beck Depression Inventory (BDI) are the most frequently used observer-rated and self-report scales of depression, respectively. It is important to know what a given total score or a change score from baseline on one scale means in relation to the other scale.

We obtained individual participant data from the randomised controlled trials of psychological and pharmacological treatments for major depressive disorders. We then identified corresponding scores of the HAMD and the BDI (369 patients from seven trials) or the BDI-II (683 patients from another seven trials) using the equipercentile linking method.

The HAMD total scores of 10, 20 and 30 corresponded approximately with the BDI scores of 10, 27 and 42 or with the BDI-II scores of 13, 32 and 50. The HAMD change scores of −20 and −10 with the BDI of −29 and −15 and with the BDI-II of −35 and −16.

The results can help clinicians interpret the HAMD or BDI scores of their patients in a more versatile manner and also help clinicians and researchers evaluate such scores reported in the literature or the database, when scores on only one of these scales are provided. We present a conversion table for future research.

Different diagnostic interviews are used as reference standards for major depression classification in research. Semi-structured interviews involve clinical judgement, whereas fully structured interviews are completely scripted. The Mini International Neuropsychiatric Interview (MINI), a brief fully structured interview, is also sometimes used. It is not known whether interview method is associated with probability of major depression classification.

To evaluate the association between interview method and odds of major depression classification, controlling for depressive symptom scores and participant characteristics.

Data collected for an individual participant data meta-analysis of Patient Health Questionnaire-9 (PHQ-9) diagnostic accuracy were analysed and binomial generalised linear mixed models were fit.

A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15–3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores ≤6) as having major depression (OR = 3.13; 95% CI = 0.98–10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7–15) (OR = 0.96; 95% CI = 0.56–1.66) and significantly less likely for high-level symptoms (PHQ-9 scores ≥16) (OR = 0.50; 95% CI = 0.26–0.97).

The MINI may identify more people as depressed than the CIDI, and semi-structured and fully structured interviews may not be interchangeable methods, but these results should be replicated.

Drs Jetté and Patten declare that they received a grant, outside the submitted work, from the Hotchkiss Brain Institute, which was jointly funded by the Institute and Pfizer. Pfizer was the original sponsor of the development of the PHQ-9, which is now in the public domain. Dr Chan is a steering committee member or consultant of Astra Zeneca, Bayer, Lilly, MSD and Pfizer. She has received sponsorships and honorarium for giving lectures and providing consultancy and her affiliated institution has received research grants from these companies. Dr Hegerl declares that within the past 3 years, he was an advisory board member for Lundbeck, Servier and Otsuka Pharma; a consultant for Bayer Pharma; and a speaker for Medice Arzneimittel, Novartis, and Roche Pharma, all outside the submitted work. Dr Inagaki declares that he has received grants from Novartis Pharma, lecture fees from Pfizer, Mochida, Shionogi, Sumitomo Dainippon Pharma, Daiichi-Sankyo, Meiji Seika and Takeda, and royalties from Nippon Hyoron Sha, Nanzando, Seiwa Shoten, Igaku-shoin and Technomics, all outside of the submitted work. Dr Yamada reports personal fees from Meiji Seika Pharma Co., Ltd., MSD K.K., Asahi Kasei Pharma Corporation, Seishin Shobo, Seiwa Shoten Co., Ltd., Igaku-shoin Ltd., Chugai Igakusha and Sentan Igakusha, all outside the submitted work. All other authors declare no competing interests. No funder had any role in the design and conduct of the study; collection, management, analysis and interpretation of the data; preparation, review or approval of the manuscript; and decision to submit the manuscript for publication.

Little is known about potential harmful effects as a consequence of self-guided internet-based cognitive behaviour therapy (iCBT), such as symptom deterioration rates. Thus, safety concerns remain and hamper the implementation of self-guided iCBT into clinical practice. We aimed to conduct an individual participant data (IPD) meta-analysis to determine the prevalence of clinically significant deterioration (symptom worsening) in adults with depressive symptoms who received self-guided iCBT compared with control conditions. Several socio-demographic, clinical and study-level variables were tested as potential moderators of deterioration.

Randomised controlled trials that reported results of self-guided iCBT compared with control conditions in adults with symptoms of depression were selected. Mixed effects models with participants nested within studies were used to examine possible clinically significant deterioration rates.

Thirteen out of 16 eligible trials were included in the present IPD meta-analysis. Of the 3805 participants analysed, 7.2% showed clinically significant deterioration (5.8% and 9.1% of participants in the intervention and control groups, respectively). Participants in self-guided iCBT were less likely to deteriorate (OR 0.62, p < 0.001) compared with control conditions. None of the examined participant- and study-level moderators were significantly associated with deterioration rates.

Self-guided iCBT has a lower rate of negative outcomes on symptoms than control conditions and could be a first step treatment approach for adult depression as well as an alternative to watchful waiting in general practice.

More than half of patients who present with depressive disorders also have elevated comorbid anxiety symptoms. Given the high comorbidity between these disorders, it is important to understand the extent that psychotherapies for depression additionally ameliorate symptoms of anxiety.

Systematic searches were conducted in PubMed, PSYCinfo, EMBASE, and the Cochrane Registry of Controlled Trials. Included studies were randomized controlled trials that compared psychotherapy compared with a control condition for the treatment of adults with a primary diagnosis or elevated symptoms of depression and that examined the effects of treatment on anxiety outcomes. Acute phase depression and anxiety (continuous measure) outcomes were extracted. Effect sizes were calculated by subtracting the average post-treatment scores of the psychotherapy group from the average post-treatment scores of the comparison group divided by the pooled standard deviation.

Fifty-two studies of varying quality met the inclusion criteria. Pooled effect sizes showed that anxiety outcomes were significantly lower in the psychotherapy conditions than in control conditions at post-treatment [g = 0.52; 95% confidence interval (CI) 0.44–0.60; NNT (numbers-needed-to-treat) = 3.50]. Moderate heterogeneity was observed (I2 = 55%, 95% CI 40–66). Bivariate metaregression analysis revealed a significant association between depression and anxiety effect sizes at post-treatment Longer-term follow-ups of up to 14 months post-baseline showed indications for a small lasting effect of psychotherapy on anxiety outcomes (g = 0.27).

This meta-analysis provides evidence that psychotherapy aimed at depression can also reduce anxiety symptoms in relation to control conditions.

It is not clear whether relaxation therapies are more or less effective than cognitive and behavioural therapies in the treatment of anxiety. The aims of the present study were to examine the effects of relaxation techniques compared to cognitive and behavioural therapies in reducing anxiety symptoms, and whether they have comparable efficacy across disorders.

We conducted a meta-analysis of 50 studies (2801 patients) comparing relaxation training with cognitive and behavioural treatments of anxiety.

The overall effect size (ES) across all anxiety outcomes, with only one combined ES in each study, was g = −0.27 [95% confidence interval (CI) = −0.41 to −0.13], favouring cognitive and behavioural therapies (number needed to treat = 6.61). However, no significant difference between relaxation and cognitive and behavioural therapies was found for generalized anxiety disorder, panic disorder, social anxiety disorder and specific phobias (considering social anxiety and specific phobias separately). Heterogeneity was moderate (I2 = 52; 95% CI = 33–65). The ES was significantly associated with age (p < 0.001), hours of cognitive and/or behavioural therapy (p = 0.015), quality of intervention (p = 0.007), relaxation treatment format (p < 0.001) and type of disorder (p = 0.008), explaining an 82% of variance.

Relaxation seems to be less effective than cognitive and behavioural therapies in the treatment of post-traumatic stress disorder, and obsessive–compulsive disorder and it might also be less effective at 1-year follow-up for panic, but there is no evidence that it is less effective for other anxiety disorders.

The influence of baseline severity has been examined for antidepressant medications but has not been studied properly for cognitive–behavioural therapy (CBT) in comparison with pill placebo.

To synthesise evidence regarding the influence of initial severity on efficacy of CBT from all randomised controlled trials (RCTs) in which CBT, in face-to-face individual or group format, was compared with pill-placebo control in adults with major depression.

A systematic review and an individual-participant data meta-analysis using mixed models that included trial effects as random effects. We used multiple imputation to handle missing data.

We identified five RCTs, and we were given access to individual-level data (n = 509) for all five. The analyses revealed that the difference in changes in Hamilton Rating Scale for Depression between CBT and pill placebo was not influenced by baseline severity (interaction P = 0.43). Removing the non-significant interaction term from the model, the difference between CBT and pill placebo was a standardised mean difference of –0.22 (95% CI –0.42 to –0.02, P = 0.03, I 2 = 0%).

Patients suffering from major depression can expect as much benefit from CBT across the wide range of baseline severity. This finding can help inform individualised treatment decisions by patients and their clinicians.

Sponsorship bias has never been investigated for non-pharmacological treatments like psychotherapy.

We examined industry funding and author financial conflict of interest (COI) in randomised controlled trials directly comparing psychotherapy and pharmacotherapy in depression.

We conducted a meta-analysis with subgroup comparisons for industry v. non-industry-funded trials, and respectively for trial reports with author financial COI v. those without.

In total, 45 studies were included. In most analyses, pharmacotherapy consistently showed significant effectiveness over psychotherapy, g = −0.11 (95% CI −0.21 to −0.02) in industry-funded trials. Differences between industry and non-industry-funded trials were significant, a result only partly confirmed in sensitivity analyses. We identified five instances where authors of the original article had not reported financial COI.

Industry-funded trials for depression appear to subtly favour pharmacotherapy over psychotherapy. Disclosure of all financial ties with the pharmaceutical industry should be encouraged.

Several meta-analyses have shown that psychotherapy is effective for reducing depressive symptom severity. However, the impact on quality of life (QoL) is as yet unknown.

To investigate the effectiveness of psychotherapy for depression on global QoL and on the mental health and physical health components of QoL.

We conducted a meta-analysis of 44 randomised clinical trials comparing psychotherapy for adults experiencing clinical depression or elevated depressive symptoms with a control group. We used subgroup analyses to explore the influence of various study characteristics on the effectiveness of treatment.

We detected a small to moderate effect size (Hedges' g = 0.33, 95% CI 0.24–0.42) for global QoL, a moderate effect size for the mental health component (g = 0.42, 95% CI 0.33–0.51) and, after removing an outlier, a small but statistically significant effect size for the physical health component (g = 0.16, 95% CI 0.05–0.27). Multivariate meta-regression analyses showed that the effect size of depressive symptoms was significantly related to the effect size of the mental health component of QoL. The effect size of depressive symptoms was not related to global QoL or the physical health component.

Psychotherapy for depression has a positive impact on the QoL of patients with depression. Improvements in QoL are not fully explained by improvements in depressive symptom severity.

Psychological interventions may be beneficial in bipolar disorder.

To evaluate the efficacy of psychological interventions for adults with bipolar disorder.

A systematic review of randomised controlled trials was conducted. Outcomes were meta-analysed using RevMan and confidence assessed using the GRADE method.

We included 55 trials with 6010 participants. Moderate-quality evidence associated individual psychological interventions with reduced relapses at post-treatment (risk ratio (RR) = 0.66, 95% CI 0.48–0.92) and follow-up (RR = 0.74, 95% CI 0.63–0.87), and collaborative care with a reduction in hospital admissions (RR =0.68, 95% CI 0.49–0.94). Low-quality evidence associated group interventions with fewer depression relapses at post-treatment and follow-up, and family psychoeducation with reduced symptoms of depression and mania.

There is evidence that psychological interventions are effective for people with bipolar disorder. Much of the evidence was of low or very low quality thereby limiting our conclusions. Further research should identify the most effective (and cost-effective) interventions for each phase of this disorder.

Cognitive bias modification (CBM) interventions are strongly advocated in research and clinical practice.

To examine the efficiency of CBM for clinically relevant outcomes, along with study quality, publication bias and potential moderators.

We included randomised controlled trials (RCTs) of CBM interventions that reported clinically relevant outcomes assessed with standardised instruments.

We identified 49 trials and grouped outcomes into anxiety and depression. Effect sizes were small considering all the samples, and mostly non-significant for patient samples. Effect sizes became non-significant when outliers were excluded and after adjustment for publication bias. The quality of the RCTs was suboptimal.

CBM may have small effects on mental health problems, but it is also very well possible that there are no significant clinically relevant effects. Research in this field is hampered by small and low-quality trials, and by risk of publication bias. Many positive outcomes are driven by extreme outliers.

There is controversy about whether psychotherapies are effective in the treatment of subclinical depression, defined by clinically relevant depressive symptoms in the absence of a major depressive disorder.

To examine whether psychotherapies are effective in reducing depressive symptoms, reduce the risk of developing major depressive disorder and have comparable effects to psychological treatment of major depression.

We conducted a meta-analysis of 18 studies comparing a psychological treatment of subclinical depression with a control group.

The target groups, therapies and characteristics of the included studies differed considerably from each other, and the quality of many studies was not optimal. Psychotherapies did have a small to moderate effect on depressive symptoms against care as usual at the post-test assessment (g = 0.35, 95% CI 0.23–0.47; NNT = 5, 95% CI 4–8) and significantly reduced the incidence of major depressive episodes at 6 months (RR = 0.61) and possibly at 12 months (RR = 0.74). The effects were significantly smaller than those of psychotherapy for major depressive disorder and could be accounted for by non-specific effects of treatment.

Psychotherapy may be effective in the treatment of subclinical depression and reduce the incidence of major depression, but more high-quality research is needed.

Past episodes of depressive or anxiety disorders and subthreshold symptoms have both been reported to predict the occurrence of depressive or anxiety disorders. It is unclear to what extent the two factors interact or predict these disorders independently.

To examine the extent to which history, subthreshold symptoms and their combination predict the occurrence of depressive (major depressive disorder, dysthymia) or anxiety disorders (social phobia, panic disorder, agoraphobia, generalised anxiety disorder) over a 2-year period.

This was a prospective cohort study with 1167 participants: the Netherlands Study of Depression and Anxiety. Anxiety and depressive disorders were determined with the Composite International Diagnostic Interview, subthreshold symptoms were determined with the Inventory of Depressive Symptomatology–Self Report and the Beck Anxiety Inventory.

Occurrence of depressive disorder was best predicted by a combination of a history of depression and subthreshold symptoms, followed by either one alone. Occurrence of anxiety disorder was best predicted by both a combination of a history of anxiety disorder and subthreshold symptoms and a combination of a history of depression and subthreshold symptoms, followed by any subthreshold symptoms or a history of any disorder alone.

A history and subthreshold symptoms independently predicted the subsequent occurrence of depressive or anxiety disorder. Together these two characteristics provide reasonable discriminative value. Whereas anxiety predicted the occurrence of an anxiety disorder only, depression predicted the occurrence of both depressive and anxiety disorders.

Many people suffer from subthreshold and mild panic disorder and are at risk of developing more severe panic disorder.

This study (trial registration: ISRCTN33407455) was conducted to evaluate the effectiveness of an early group intervention based on cognitive–behavioural principles to reduce panic disorder symptomatology.

Participants with subthreshold or mild panic disorder were recruited from the general population and randomised to the intervention (n = 109) or a waiting-list control group (n = 108). The course was offered by 17 community mental health centres.

In the early intervention group, 43/109 (39%) participants presented with a clinically significant change on the Panic Disorder Severity Scale–Self Report (PDSS–SR) v. 17/108 (16%) in the control group (odds ratio (OR) for favourable treatment response 3.49, 95% CI 1.77–6.88, P = 0.001). The course also had a positive effect on DSM–IV panic disorder status (OR = 1.96, 95% CI=1.05–3.66, P = 0.037). The PDSS–SR symptom reduction was also substantial (between-group standardised mean difference of 0.68). The effects were maintained at 6-month follow-up.

People presenting with subthreshold and mild panic disorder benefit from this brief intervention.