EpiReumaPt: how to perform a national population based study - a practical guide.

BACKGROUND: The aim of this article was to describe and discuss several strategies and standard operating procedures undertaken in the EpiReumaPt study - which was the first Portuguese, national, cross-sectional population-based study of Rheumatic and Musculoskeletal Diseases (RMD). METHODS: The technical procedures, legal issues, management and practical questions were studied, analyzed and discussed with relevant stakeholders. During the 1st phase of EpiReumaPt the coordination team and Centro de Estudos de Sondagens e Opinião (CESOP) worked to recruit and interview 10,661 subjects. The 2nd phase involved the participation of a multidisciplinary team, several local authorities, a specialized vehicle ("mobile unit") and a specific software program for the clinical appointments. The development of specific recruitment strategies improved the participation rate. Blood samples were collected and sent to Biobanco-IMM and to a central lab for immediate measurements. In the 3rd phase the RMD diagnosis were validated by a team of three experienced rheumatologists - clinical data, imaging and lab test results were revised according to previously published classification criteria. CONCLUSION: EpiReumaPt was a nationwide project successfully conducted, which followed critical logistic/coordination and research strategies. EpiReumaPt methodology and coordination could be used as an example for other epidemiologic endeavors and public health policies.