1. Primary Care Research Unit, the Alamedilla Health Center
2. Castilla and León Health Service–SACYL Salamanca
3. Medicine Department, University of Salamanca
4. Statistics Department, University of Salamanca
5. CS G. Corsaib, Primare Care Ibsalut
6. Research Unit, Family Medicine, Girona. Jordi Gol Institute for Primary Care Research (IDIAP Jordi Gol)
7. Trans Research Group. Department of Medical Sciences, School of Medicine, University of Girona
8. Girona Biomedical Research Institute (IDIBGI), Dr. Trueta University Hospital