1. Department of Medical Biochemistry; Dokuz Eylül University Medical Faculty; Izmir Turkey
2. Working Group on Drug Abuse Testing; Turkish Ministry of Health; Turkey
3. Turkish Ministry of Health; Ankara Turkey
4. Kayseri Training and Research Hospital, Biochemistry Laboratory; Kayseri Turkey
5. Biochemistry Laboratory; Ankara Training and Research Hospital; Ankara Turkey
6. Department of Medical Biochemistry; Hacettepe University Medical Faculty; Ankara Turkey
7. Biochemistry Laboratory; Ordu State Hospital; Ordu Turkey
8. Department of Public Health; Dokuz Eylül University Medical Faculty; Izmir Turkey
9. Department of Laboratory Medicine, and Department of Clinical Chemistry, Microbiology and Immunology, Ghent University; Ghent University Hospital; Ghent Belgium
10. Doğu Akdeniz University Pharmacy Faculty; Gazimagosa Cyprus