1. Service of Clinical Analysis and Biochemistry , Hospital Universitario San Jorge , Huesca , Spain
2. Service of Biochemistry , Clínica Universidad de Navarra , Pamplona , Spain
3. Service of Biochemistry-Clinical Analysis , Hospital Universitario Puerta de Hierro , Majadahonda , Spain
4. CATLAB Central Laboratory , Barcelona , Spain
5. Service of Clinical Analysis , Hospital Universitario La Paz , Madrid , Spain
6. Service of Clinical Analysis , Hospital Universitario Arnau de Vilanova , Lleida , Spain
7. Service of Biochemistry-Clinical Analysis , Hospital Universitario Virgen Macarena , Sevilla , Spain