The purpose of this study is to perform an efficacy study of Personal Construct Therapy, which focuses on the construction of self and others, for women diagnosed with fibromyalgia who have also comorbid depressive symptoms. To that aim, it will be compared with Cognitive Behavioral Therapy, which is an already well-established treatment in this area.

Fibromyalgia is one of the most demanding health issues nowadays due to the high level of suffering and the deterioration of quality of life it entails. In addition, its high prevalence and the great expenses it implies for social and health care systems are also matter of both public and politic concern.

Previous research has shown that the personal affliction triggered by fibromyalgia is influenced by psychological factors, which have also an effect on the socioeconomic burden of this disease as a consequence. Among these factors, depressive symptoms are highlighted in this study not only because they exacerbate the clinical profile of this type of patients, but also because they decrease their response to treatment, contributing to the chronicity of this disease. In fact, the treatment of depressive symptoms is already one of the therapeutic targets included in the most recommended multicomponent (and multidisciplinary) treatment guidelines for fibromyalgia.

In spite of the growing number of studies supporting the efficacy of psychological therapies for fibromyalgia, many issues need further development. For example, current treatment recommendations for this syndrome suggest that the intervention must be tailored to the psychosocial and functioning profile of patients. However, research is still needed in order to enable the identification of key factors for clinical improvement. Similarly, it is crucial to identify and assess idiosyncratic psychological characteristics that may allow the psychological intervention to be effectively adapted. In addition, an evidence-based description of the mechanisms involved in change at different levels (including psychological and physical ones) has not been developed yet.

The aim of this project is to perform an efficacy study of Personal Construct Therapy (PCT), which focuses on the construction of self and others, for women diagnosed with fibromyalgia who have also comorbid depressive symptoms. It will be compared with Cognitive Behavioral Therapy (CBT), which is a well-established treatment in this area. Both interventions will be performed in individual format. Depressive symptoms will be measured before and after treatments, along with other clinical and wellbeing-related variables. The cognitive indexes derived from the Repertory Grid Technique, such as cognitive conflicts, polarization and self-construction measures, will also be assessed. Moreover, the capacity of all these measures for predicting differential outcomes resulting from both treatments will also be estimated. The relevance of these cognitive indicators for depression and fibromyalgia has already been proven by this research group in previous studies.

It is expected that PCT will be more effective than standard CBT in improving clinical symptoms and wellbeing. Additionally, the identification of patients' cognitive characteristics which may have a differential response to the components of each treatment will allow future adaptation of psychological interventions to the characteristics of patients, which will contribute in turn to the improvement of the existing treatments.

Inclusion Criteria:

• Diagnosis of fibromyalgia in the health care system
• A score above 7 on the Hospital Anxiety and Depression Scales

Exclusion Criteria:

• Bipolar disorders
• Psychotic symptoms
• Substance abuse
• Organic brain dysfunction
• Mental retardation
• Serious suicidal ideation
• Receiving psychological treatment (unless it is suspended at the time of inclusion in the study)
• Inability to communicate in Spanish
• Substantial visual, hearing or cognitive deficits