1. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain
2. External Quality Assurance Programs, SEQCML, Barcelona, Spain
3. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; La Paz University Hospital, Madrid, Spain
4. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; Clinical Laboratory, Hospital Campus de la Salud, Granada, Spain
5. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; Intercomarcal laboratory consortiums of Alt Penedès, Anoia and Garraf, Barcelona, Spain
6. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; Department of Clinical Biochemistry, University Hospital of Salamanca, Salamanca, Spain
7. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; Metropolitana Nord Unified Laboratory (LUMN), Germans Trias I Pujol University Hospital, Badalona, Spain
8. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; Clinical Analysis Service, Hospital San Agustin, Aviles, Principality of Asturias, Spain
9. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; Quality Healthcare Consulting, ACMS Group, Madrid, Spain
10. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; Aragonese Health Service, Royo Villanova Hospital, Zaragoza, Spain
11. Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain; Clinical Laboratory Department, Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain