National rare diseases registry in Spain: pilot study of the Spanish Rare Diseases Registries Research Network (SpainRDR) - Alonso, Verónica; Abaitua, Ignacio; Zurriaga, Óscar; Astray, Jenaro; Errezola, Manuel; Aldana-Espinal, Josefa M; Margolles, Mario J; Jiménez, Josep; Palomar, Joaquín A; Santana, Milagrosa; Ramalle-Gomarra, Enrique; Ramos, Julián M; et al. (Orphanet Journal of Rare Diseases, 2014)