BIOBADASER, BIOBADAMERICA, and BIOBADADERM: safety registers sharing commonalities across diseases and countries.

Registers facilitate the collection and communication of safety concerns. There are as many different register structures as registers, making the merging of rare data and comparison between registers difficult. BIOBADASER, the Safety Register of the Spanish Society of Rheumatology has served as template for other registers within the specialty, BIOBADAMERICA, and outside rheumatology, BIOBADADERM. Here we present the limitations and strengths of such template registers.