Although several studies have illustrated the effectiveness of cognitive behavior therapy (CBT) on adult pain patients, there are few randomized controlled trials on children and adolescents. There is particularly a need for studies on pediatric patients who are severely disabled by longstanding pain syndromes. Acceptance and Commitment Therapy, as an extension of traditional CBT, focuses on improving functioning and quality of life by increasing the patient's ability to act effectively in concordance with personal values also in the presence of pain and distress. Following a pilot study, we sought to evaluate the effectiveness of an ACT-oriented intervention based on exposure and acceptance strategies and to compare this with a multidisciplinary treatment approach including amitriptyline (n=32). The ACT condition underwent a relatively brief treatment protocol of approximately 10 weekly sessions. Assessments were made before and immediately after treatment, as well as at 3.5 and 6.5 months follow-up. Prolonged treatment in the MDT group complicated comparisons between groups at follow-up assessments. Results showed substantial and sustained improvements for the ACT group. When follow-up assessments were included, ACT performed significantly better than MDT on perceived functional ability in relation to pain, pain intensity and to pain-related discomfort (intent-to-treat analyses). At post-treatment, significant differences in favor of the ACT condition were also seen in fear of re/injury or kinesiophobia, pain interference and in quality of life. Thus, results from the present study support previous findings and suggest the effectiveness of this ACT-oriented intervention for pediatric longstanding pain syndromes.

The results correspond with previous studies on ACT for chronic pain and suggest the utility of ACT for FM as well as the role of psychological inflexibility as a mediator of improvement.

Cognitive behavior therapy (CBT) has made important contributions to chronic pain management, but the process by which it is effective is not clear. Recently, strong arguments have been raised concerning the need for theory driven research to e.g. identify mechanisms of change in CBT and enhance the effectiveness of this type of treatment. However, the number of studies addressing these issues is still relatively scarce. Furthermore, the arrival of varieties of CBT with seemingly different process targets increases the need for such information. The present study explored the processes of change in a previously reported successful randomized controlled trial evaluating the effectiveness of an exposure-based form of behavioral and cognitive therapy, Acceptance and Commitment Therapy (ACT), on improvement in pain-related disability and life satisfaction for patients suffering from whiplash-associated disorder (WAD). Several process variables relevant to theories underlying traditional CBT were included: pain, distress, kinesiophobia, self-efficacy, and the process primarily targeted by ACT: psychological inflexibility. Mediation analyses were performed using a non-parametric cross-product of the coefficients approach. Results illustrated that pain intensity, anxiety, depression, kinesiophobia, and self-efficacy did not have significant mediating effects on the dependent variables. In contrast, significant indirect effects were seen for psychological inflexibility on pain-related disability (pre- to post-change scores) and life satisfaction (pre- to post; pre- to 4-month follow-up change scores). Although tentative, these results support the mediating role of psychological inflexibility in ACT-oriented interventions aimed at improving functioning and life satisfaction in people with chronic pain.

Interventions based on Cognitive Behavioral Therapy (CBT) are widely used to treat chronic pain, but the brain mechanisms responsible for these treatment effects are poorly understood. The aim of this study was to validate the relevance of the cortical control theory in response to an exposure-based form of CBT, Acceptance and Commitment Therapy, in patients with chronic pain. Forty-three female patients diagnosed with fibromyalgia syndrome were enrolled in a randomized, 12-week, waiting-list controlled clinical trial (CBT n=25; controls n=18). CBT was administered in groups of six patients during 12 weekly sessions. Functional magnetic resonance imaging (fMRI) during pressure-evoked pain was assessed before and after treatment or the 12-week period. Self-report questionnaires of depression and anxiety were administered pre- and posttreatment as well as 3 months following end of treatment. Patients treated with CBT reported larger improvement of fibromyalgia on the Patient Global Impression of Change measure, and improved depression and anxiety symptoms, compared to the waiting-list controls. However, there were no effects on clinical pain or pain sensitivity measures. An analysis of fMRI scans revealed that CBT led to increased activations in the ventrolateral prefrontal/lateral orbitofrontal cortex; regions associated with executive cognitive control. We suggest that CBT changes the brain's processing of pain through an altered cerebral loop between pain signals, emotions, and cognitions; leading to increased access to executive regions for reappraisal of pain. Our data thereby support our hypothesis about the activation of a cortical control mechanism in response to CBT treatment in chronic pain.

Recent developments within CBT have emphasized acceptance rather than control of pain and distress in treatments aimed at improving functioning and life quality, but there is still a lack of reliable and valid instruments to assess relevant processes in such interventions. The Psychological Inflexibility in Pain Scale (PIPS) was developed to assess target variables in exposure and acceptance oriented treatments. A preliminary validation study resulted in a two-factor solution with subscales for avoidance and cognitive fusion related to pain, showing satisfactory psychometric properties. This study sought to evaluate the instrument with 611 participants with whiplash associated disorders. Exploratory and confirmatory factor analyses supported a two-factor solution with 12 items which showed an acceptable model fit, adequate internal consistencies, and strong relations with criteria variables (e.g. disability and life satisfaction). The construct validity of the instrument was supported by high correlations with subscales from the Chronic Pain Acceptance Questionnaire (CPAQ) and the Tampa Scale of Kinesiophobia (TSK). Notably, hierarchical regression analyses illustrated that PIPS explained more variance than TSK in pain, disability, life satisfaction and depression. Furthermore, PIPS was found to mediate the relationship between e.g. pain and disability, suggesting the usefulness of PIPS as a process measure in treatments of people with chronic pain. Thus, it is argued that this 12-item version of PIPS may be used to explore the importance of psychological in/flexibility in chronic pain and to analyse processes of change in exposure based interventions, as well as for clinicians in tailoring interventions for patients with chronic debilitating pain.

Although 14% to 42% of people with whiplash injuries end up with chronic debilitating pain, there is still a paucity of empirically supported treatments for this group of patients. In chronic pain management, there is increasing consensus regarding the importance of a behavioural medicine approach to symptoms and disability. Cognitive behaviour therapy has proven to be beneficial in the treatment of chronic pain. An approach that promotes acceptance of, or willingness to experience, pain and other associated negative private events (e.g. fear, anxiety, and fatigue) instead of reducing or controlling symptoms has received increasing attention. Although the empirical support for treatments emphasizing exposure and acceptance (such as acceptance and commitment therapy) is growing, there is clearly a need for more outcome studies, especially randomized controlled trials. In this study, participants (N = 21) with chronic pain and whiplash-associated disorders were recruited from a patient organization and randomized to either a treatment or a wait-list control condition. Both groups continued to receive treatment as usual. In the experimental condition, a learning theory framework was applied to the analysis and treatment. The intervention consisted of a 10-session protocol emphasizing values-based exposure and acceptance strategies to improve functioning and life satisfaction by increasing the participants' abilities to behave in accordance with values in the presence of interfering pain and distress (psychological flexibility). After treatment, significant differences in favor of the treatment group were seen in pain disability, life satisfaction, fear of movements, depression, and psychological inflexibility. No change for any of the groups was seen in pain intensity. Improvements in the treatment group were maintained at 7-month follow-up. The authors discuss implications of these findings and offer suggestions for further research in this area.

Acceptance of pain and other associated negative private experiences has received increasing attention in recent years. This approach is in stark contrast to the traditional approach of reducing or controlling symptoms of pain. The empirical support for treatments emphasizing exposure and acceptance, such as Acceptance and Commitment Therapy, is growing. However, to date, few instruments exist to assess the core processes in these types of treatments. This study describes the development and preliminary validation of the Psychological Inflexibility in Pain Scale. Principal components analysis (PCA) suggests a 2-factor solution with a total of 16 items measuring avoidance of pain and cognitive fusion with pain. Results also indicate adequate reliability and validity for the scale. Implications of these findings for clinical assessment, as well as for research on pain related disability, are discussed along with suggestions for further research in this area.

Even though psychological interventions are well established in the treatment of pediatric chronic pain, there is a clear need for further development, especially with severely disabled patients. However, optimizing effectiveness in psychological treatments for pain requires clarification of the mechanisms of action. Studies addressing change processes are scarce, however, particularly in relation to pediatric chronic pain. Acceptance and Commitment Therapy (ACT), as an extension of traditional cognitive behavior therapy, is essentially aimed at improving functioning by increasing the ability to act effectively in the presence of pain and distress, that is, psychological flexibility. ACT has shown promising results for both adult and pediatric chronic pain. In the present study, the mediators of change in an ACT-oriented treatment for pediatric chronic pain were examined using a bootstrapped cross product of coefficients approach. Pain interference and depression were used as outcome variables. Six different variables relevant to theories underlying ACT and cognitive behavior therapy were included in the analyses as possible mediators of change: pain impairment beliefs, pain reactivity, self-efficacy, kinesiophobia, catastrophizing, and pain intensity. Results illustrated that pain impairment beliefs and pain reactivity were the only variables that significantly mediated the differential effects of treatment on outcomes at follow-up. Also, these 2 mediators were shown to independently predict effects in outcome variables at follow-up while controlling for earlier effects in outcome, but only for the ACT condition. Although tentative, the pattern of results suggests that variables consistent with psychological flexibility mediate the effects of ACT-based interventions to improve functioning in patients with chronic debilitating pain.