Introduction: Minor psychiatric disorders are important in primary care, because of its high prevalence and consumption of healthcare resources generated.

Objective: Evaluate the effectiveness of rational emotive behavioral therapy (REBT), as an instrument of social work intervention to enhance changes in the parameters of quality of life, medical consultations and drug use in patients with dysthymia.

Design: Multicenter, prospective, not randomized clinical trial, with intervention and control group simultaneously in urban primary care settings and 1 year of follow up.

Participants: Out-patients seen in two Primary Care centers diagnosed with dysthymia according to DSM-IV classification of American Psychiatric Association.

Intervention: Subjects receive up to 8 biweekly individual sessions of thirty minutes of REBT administered by the Social Worker.

Variables: Demographic data, educational level, coexistence, comorbidity, quality of life assessment, severity of depression, number of visits to the General Practitioner (GP) and drug consumption: sedatives / antidepressants.

Expected Results: The expected results of the intervention, estimated from previous data, are:

• A decrease in attendance at medical visits per year
• An improvement in perceived quality of life, measured as values of the Quality of Life (QOL) questionnaire (Baker & Intagliata)
• An improvement in severity of depression, measured according to the Beck Depression Inventory.
• A reduction of treatment with psychotropic drugs (sedatives and antidepressants).

Potential impact expected: The investigators hope that rational emotive theory is an effective intervention method for handling minor psychiatric disorders in clinical social work.

The calculation of the size of the population sample was performed for the worst case comparison of different outcome variables, so for a final ratio of 8% people taking hypnotics in Intervention Group (IG) versus 37% in the Control Group (CG), with significance level of 5% and a statistical power of 80%, previewing a 20% loss to follow-up and a ratio of 1 control per case, we need 50 individuals in the CG and 50 individuals in the IG.

Regarding to the attendance to primary care centers, was categorized as "improved" and "not improved or remains the same." "Improvement" is when the number of visits decrease over the previous year, comparing baseline data with respect 12 months. Also, improvement in the use of psychotropic medication is when intakes fall in the previous year by comparing baseline data with respect 12 months. When no data were available at 12 months, the comparison was made with data collected at 4 months.

Patients in IG were recruited from primary care center Sant Andreu, while the CG were enrolled in the primary care center in Martorell. The selection of the two groups in separate centers was determined to avoid the possible effects of contamination bias of the CBT-REBT. In the IG, each physician systematically derived patients with inclusion criteria to the social worker. In the CG, the physician made ordinary care task. In both groups, the number of visits to primary care centers and consumption of psychotropic drugs were extracted from the medical record and other information was obtained through interviews at baseline, 4 and 12 months.

All patients signed informed consent at baseline. In order to recruit homogeneous cases, clearly diagnosed and ensure comparability training for all recruiters was conducted. Collection forms and the database did not include confidential information to ensure confidentiality and anonymity, keeping a separately single list with relation to the number of each case.

Access data base was used to systematize the registration data collection and handling errors by different professionals. Previous comparison of baseline data between completers and dropouts, as well as between the IG and CG was performed by Chi-square and mean comparison. A descriptive analysis of baseline variables as frequencies, means, and dispersion measures was carried out. For the analysis of post-intervention improvement in outcome parameters in one group compared with another, only data from the baseline and 12 months were taken into account. Bivariate and multivariate analysis was performed using logistic regression to control for confounding factors. Values less than 0.05 were considered significant. The Statistical Package for the Social Sciences (SPSS) v.18 software was used.

Inclusion Criteria:

• Clinical diagnosis fo dysthymia
• Aged 14 or older

Exclusion Criteria:

• Impaired cognitive ability
• Illiteracy
• Refuses treatment
• Severe psychiatric disorders
• Participation in psychoeducational groups or other similar therapies.