Open Access Study protocol

Assessment of an enhanced program for depression management in primary care: a cluster randomized controlled trial. The INDI project (Interventions for Depression Improvement)

Enric Aragonès14*, Antonia Caballero1, Josep Ll Piñol1, Germán López-Cortacans1, Waleska Badia1, Josep M Hernández1, Pilar Casaus2, Sílvia Folch1, Josep Basora1, Antonio Labad23 and the INDI research group

Author Affiliations

1 Tarragona-Reus Primary Care Area, Catalan Health Institute, Spain

2 University Psychiatric Hospital "Institut Pere Mata", Reus, Spain

3 Unit of Psychiatry, Rovira i Virgili University, Reus, Spain

4 Centre d'Atenció Primària de Constantí; Carrer dels Horts, 6. 43120 Constantí (Tarragona), Spain

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BMC Public Health 2007, 7:253  doi:10.1186/1471-2458-7-253

Published: 20 September 2007



Most depressed patients are attended at primary care. However, there are significant shortcomings in the diagnosis, management and outcomes of these patients. The aim of this study is to determine whether the implementation of a structured programme for managing depression will provide better health outcomes than usual management.


Design: A cluster-randomized controlled trial involving two groups, one of which is the control group consisting of patients who are treated for depression in the usual way and the other is the intervention group consisting of patients on a structured programme for treating depression.

Setting: 20 primary care centres in the province of Tarragona (Spain)

Sample: 400 patients over 18 years of age who have experienced an episode of major depression (DSM-IV) and who need to initiate antidepressant treatment

Intervention: A multi-component programme with clinical, educational and organisational procedures that includes training for the health care provider and evidence-based clinical guidelines. It also includes primary care nurses working as care-managers who provide educational and emotional support for the patients and who are responsible for active and systematic clinical monitoring. The programme aims to improve the primary care/specialized level interface.

Measurements: The patients will be monitored by telephone interviews. The interviewer will not know which group the patient belongs to (blind trial). These interviews will be given at 0, 3, 6 and 12 months.

Main variables: Severity of the depressive symptoms, response rate and remission rate.

Analysis: Outcomes will be analyzed on an intent-to-treat basis and the unit of analysis will be the individual patient. This analysis will take into account the effect of study design on potential lack of independence between observations within the same cluster.


The effectiveness of caring for depression in primary care can be improved by various strategies. The most effective models involve organisational changes and a greater role of nurses. However, these models are almost exclusively from the USA, and this randomized clinical trial will determine if this approach could be effective to improve the outcomes of depression in primary care in the Spanish health care system.

Trial registration