1. Peptide Hormones Supraregional Assay Service (SAS); Department of Clinical Biochemistry; Royal Surrey County Hospital NHS Trust; Guildford UK
2. Faculty of Health and Medical Sciences; University of Surrey; Guildford UK
3. Department of Pathology; Clinical Biochemistry; King Abdulaziz Medical City; Jeddah Saudi Arabia
4. King Abdullah International Medical Research Center (KAIMRC); College of Medicine; King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS); Jeddah Saudi Arabia