Clara Strauss

How do mindfulness-based cognitive therapy and mindfulness-based stress reduction improve mental health and wellbeing? A systematic review and meta-analysis of mediation studies

Given the extensive evidence base for the efficacy of mindfulness-based stress reduction (MBSR) and mindfulness-based cognitive therapy (MBCT), researchers have started to explore the mechanisms underlying their therapeutic effects on psychological outcomes, using methods of mediation analysis. No known studies have systematically reviewed and statistically integrated mediation studies in this field. The present study aimed to systematically review mediation studies in the literature on mindfulness-based interventions (MBIs), to identify potential psychological mechanisms underlying MBCT and MBSRs effects on psychological functioning and wellbeing, and evaluate the strength and consistency of evidence for each mechanism. For the identified mechanisms with sufficient evidence, quantitative synthesis using two-stage meta-analytic structural equation modelling (TSSEM) was used to examine whether these mechanisms mediate the impact of MBIs on clinical outcomes. This review identified strong, consistent evidence for cognitive and emotional reactivity, moderate and consistent evidence for mindfulness, rumination, and worry, and preliminary but insufficient evidence for self-compassion and psychological flexibility as mechanisms underlying MBIs. TSSEM demonstrated evidence for mindfulness, rumination and worry as significant mediators of the effects of MBIs on mental health outcomes. Most reviewed mediation studies have several key methodological shortcomings which preclude robust conclusions regarding mediation. However, they provide important groundwork on which future studies could build.

Mindfulness-Based Interventions for People Diagnosed with a Current Episode of an Anxiety or Depressive Disorder: A Meta-Analysis of Randomised Controlled Trials

Objective Mindfulness-based interventions (MBIs) can reduce risk of depressive relapse for people with a history of recurrent depression who are currently well. However, the cognitive, affective and motivational features of depression and anxiety might render MBIs ineffective for people experiencing current symptoms. This paper presents a meta-analysis of randomised controlled trials (RCTs) of MBIs where participants met diagnostic criteria for a current episode of an anxiety or depressive disorder. Method Post-intervention between-group Hedges g effect sizes were calculated using a random effects model. Moderator analyses of primary diagnosis, intervention type and control condition were conducted and publication bias was assessed. Results Twelve studies met inclusion criteria (n = 578). There were significant post-intervention between-group benefits of MBIs relative to control conditions on primary symptom severity (Hedges g = −0.59, 95% CI = −0.12 to −1.06). Effects were demonstrated for depressive symptom severity (Hedges g = −0.73, 95% CI = −0.09 to −1.36), but not for anxiety symptom severity (Hedges g = −0.55, 95% CI = 0.09 to −1.18), for RCTs with an inactive control (Hedges g = −1.03, 95% CI = −0.40 to −1.66), but not where there was an active control (Hedges g = 0.03, 95% CI = 0.54 to −0.48) and effects were found for MBCT (Hedges g = −0.39, 95% CI = −0.15 to −0.63) but not for MBSR (Hedges g = −0.75, 95% CI = 0.31 to −1.81). Conclusions This is the first meta-analysis of RCTs of MBIs where all studies included only participants who were diagnosed with a current episode of a depressive or anxiety disorder. Effects of MBIs on primary symptom severity were found for people with a current depressive disorder and it is recommended that MBIs might be considered as an intervention for this population.

A randomised controlled trial of a brief online mindfulness-based intervention

OBJECTIVES There is growing evidence that mindfulness has positive consequences for both psychological and physical health in both clinical and non-clinical populations. The potential benefits of mindfulness underpin a range of therapeutic intervention approaches designed to increase mindfulness in both clinical and community contexts. Self-guided mindfulness-based interventions may be a way to increase access to the benefits of mindfulness. This study explored whether a brief, online, mindfulness-based intervention can increase mindfulness and reduce perceived stress and anxiety/depression symptoms within a student population. METHOD One hundred and four students were randomly allocated to either immediately start a two-week, self-guided, online, mindfulness-based intervention or a wait-list control. Measures of mindfulness, perceived stress and anxiety/depression were administered before and after the intervention period. RESULTS Intention to treat analysis identified significant group by time interactions for mindfulness skills, perceived stress and anxiety/depression symptoms. Participation in the intervention was associated with significant improvements in all measured domains, where no significant changes on these measures were found for the control group. CONCLUSIONS This provides evidence in support of the feasibility and effectiveness of shorter self-guided mindfulness-based interventions. The limitations and implications of this study for clinical practice are discussed.

Can mindfulness and acceptance be learnt by self-help?: A systematic review and meta-analysis of mindfulness and acceptance-based self-help interventions

There is growing evidence that mindfulness and acceptance-based interventions have positive consequences for psychological and physical health. The most well-established of these interventions typically involve relatively large resource commitments, in terms of both the provider and participant. A number of recent studies have begun to explore whether the benefits of such interventions can be generalised to less intensive methods. Methods include pure and guided self-help utilising resources such as books and workbooks, computer programmes and applications and audio-visual materials. This paper presents a systematic review and meta-analysis of studies that have evaluated the effectiveness and acceptability of low-intensity interventions including mindfulness and acceptance-based components. Fifteen RCTs (7 ACT-based, 4 mindfulness-based and 4 multi-component interventions including elements of mindfulness and/or acceptance) were identified and reviewed. Interventions that included mindfulness and/or acceptance-based components produced significant benefits in comparison to control conditions on measures of mindfulness/acceptance, depression and anxiety with small to medium effect sizes. Engagement with the self-help interventions varied but on average two-thirds of participants completed post-intervention measures. Emerging research into low-intensity mindfulness and acceptance-based interventions is hopeful. Recommendations for research and practice are presented.

Psychological Therapies for Auditory Hallucinations (Voices): Current Status and Key Directions for Future Research

This report from the International Consortium on Hallucinations Research considers the current status and future directions in research on psychological therapies targeting auditory hallucinations (hearing voices). Therapy approaches have evolved from behavioral and coping-focused interventions, through formulation-driven interventions using methods from cognitive therapy, to a number of contemporary developments. Recent developments include the application of acceptance- and mindfulness-based approaches, and consolidation of methods for working with connections between voices and views of self, others, relationships and personal history. In this article, we discuss the development of therapies for voices and review the empirical findings. This review shows that psychological therapies are broadly effective for people with positive symptoms, but that more research is required to understand the specific application of therapies to voices. Six key research directions are identified: (1) moving beyond the focus on overall efficacy to understand specific therapeutic processes targeting voices, (2) better targeting psychological processes associated with voices such as trauma, cognitive mechanisms, and personal recovery, (3) more focused measurement of the intended outcomes of therapy, (4) understanding individual differences among voice hearers, (5) extending beyond a focus on voices and schizophrenia into other populations and sensory modalities, and (6) shaping interventions for service implementation.

Group person-based cognitive therapy for distressing voices: Pilot data from nine groups.

The present study examines the impact of group Person-Based Cognitive Therapy (PBCT) for distressing voices within an uncontrolled evaluation. In particular it utilizes a framework of acceptance of voices and self to enhance well-being and reduce distress and perceived voice-control. Sixty-two participants entered one of nine PBCT groups conducted over 8-12 sessions. Fifty participants completed therapy. Measures of well-being, distress, control and relating characteristics were completed pre- and post-therapy and at brief follow-up. Data were subjected to an intention-to-treat analysis. The groups achieved significant benefits in terms of well-being, distress, control and dependence upon the voice. The present study is the first to report significant improvement in both distress and control. Consequently, Group PBCT for distressing voices may prove a useful addition to existing psychological interventions and is worthy of further investigation. The findings are discussed in relation to clinical implications and limitations.

What is compassion and how can we measure it? A review of definitions and measures

The importance of compassion is widely recognized and it is receiving increasing research attention. Yet, there is lack of consensus on definition and a paucity of psychometrically robust measures of this construct. Without an agreed definition and adequate measures, we cannot study compassion, measure compassion or evaluate whether interventions designed to enhance compassion are effective. In response, this paper proposes a definition of compassion and offers a systematic review of self- and observer-rated measures. Following consolidation of existing definitions, we propose that compassion consists of five elements: recognizing suffering, understanding the universality of human suffering, feeling for the person suffering, tolerating uncomfortable feelings, and motivation to act/acting to alleviate suffering. Three databases were searched (Web of Science, PsycInfo, and Medline) and nine measures included and rated for quality. Quality ratings ranged from 2 to 7 out of 14 with low ratings due to poor internal consistency for subscales, insufficient evidence for factor structure and/or failure to examine floor/ceiling effects, test-retest reliability, and discriminant validity. We call our five-element definition, and if supported, the development of a measure of compassion based on this operational definition, and which demonstrates adequate psychometric properties.

Better than mermaids and stray dogs? Subtyping auditory verbal hallucinations and its implications for research and practice

The phenomenological diversity of auditory verbal hallucinations (AVH) is not currently accounted for by any model based around a single mechanism. This has led to the proposal that there may be distinct AVH subtypes, which each possess unique (as well as shared) underpinning mechanisms. This could have important implications both for research design and clinical interventions because different subtypes may be responsive to different types of treatment. This article explores how AVH subtypes may be identified at the levels of phenomenology, cognition, neurology, etiology, treatment response, diagnosis, and voice hearer’s own interpretations. Five subtypes are proposed; hypervigilance, autobiographical memory (subdivided into dissociative and nondissociative), inner speech (subdivided into obsessional, own thought, and novel), epileptic and deafferentation. We suggest other facets of AVH, including negative content and form (eg, commands), may be best treated as dimensional constructs that vary across subtypes. After considering the limitations and challenges of AVH subtyping, we highlight future research directions, including the need for a subtype assessment tool.

Examining the factor structure of the 39-item and 15-item versions of the Five Facet Mindfulness Questionnaire before and after mindfulness-based cognitive therapy for people with recurrent depression.

Research into the effectiveness and mechanisms of mindfulness-based interventions (MBIs) requires reliable and valid measures of mindfulness. The 39-item Five Facet Mindfulness Questionnaire (FFMQ-39) is a measure of mindfulness commonly used to assess change before and after MBIs. However, the stability and invariance of the FFMQ factor structure have not yet been tested before and after an MBI; pre to post comparisons may not be valid if the structure changes over this period. Our primary aim was to examine the factor structure of the FFMQ-39 before and after mindfulness-based cognitive therapy (MBCT) in adults with recurrent depression in remission using confirmatory factor analysis (CFA). Additionally, we examined whether the factor structure of the 15-item version (FFMQ-15) was consistent with that of the FFMQ-39, and whether it was stable over MBCT. Our secondary aim was to assess the general psychometric properties of both versions. CFAs showed that pre-MBCT, a 4-factor hierarchical model (excluding the “observing” facet) best fit the FFMQ-39 and FFMQ-15 data, whereas post-MBCT, a 5-factor hierarchical model best fit the data for both versions. Configural invariance across the time points was not supported for both versions. Internal consistency and sensitivity to change were adequate for both versions. Both FFMQ versions did not differ significantly from each other in terms of convergent validity. Researchers should consider excluding the Observing subscale from comparisons of total scale/subscale scores before and after mindfulness interventions. Current findings support the use of the FFMQ-15 as an alternative measure in research where briefer forms are needed.

Can we respond mindfully to distressing voices? A systematic review of evidence for engagement, acceptability, effectiveness and mechanisms of change for mindfulness-based interventions for people distressed by hearing voices

Adapted mindfulness-based interventions (MBIs) could be of benefit for people distressed by hearing voices. This paper presents a systematic review of studies exploring this possibility and we ask five questions: (1) Is trait mindfulness associated with reduced distress and disturbance in relation to hearing voices? (2) Are MBIs feasible for people distressed by hearing voices? (3) Are MBIs acceptable and safe for people distressed by hearing voices? (4) Are MBIs effective at reducing distress and disturbance in people distressed by hearing voices? (5) If effective, what are the mechanisms of change through which MBIs for distressing voices work? Fifteen studies were identified through a systematic search (n = 479). In relation to the five review questions: (1) data from cross-sectional studies showed an association between trait mindfulness and distress and disturbance in relation to hearing voices; (2) evidence from qualitative studies suggested that people distressed by hearing voices could engage meaningfully in mindfulness practice; (3) MBIs were seen as acceptable and safe; (4) there were no adequately powered RCTs allowing conclusions about effectiveness to be drawn; and (5) it was not possible to draw on robust empirical data to comment on potential mechanisms of change although findings from the qualitative studies identified three potential change processes; (i) reorientation of attention; (ii) decentring; and (iii) acceptance of voices. This review provided evidence that MBIs are engaging, acceptable, and safe. Evidence for effectiveness in reducing distress and disturbance is lacking however. We call for funding for adequately powered RCTs that will allow questions of effectiveness, maintenance of effects, mechanisms of change and moderators of outcome to be definitively addressed.