References
- The N ID. A guidelines Federal Register 1988 (53); 69 and Amendment. Federal Register 1993; 58: 6062–72
- Hansen H J, Caudill S P, Boone D J. Crisis in Drug Testing. Results of CDC Blind Study. JAMA 1985; 253: 2382–7
- Frings C S, Battaglia D J, White R M. Status of Drugs-of-abuse Testing in Urine under Blind Conditions: an AACC Study. Clin Chem 1989; 35: 891–4
- Segura J, Torredl R, Congost M, Cami J. Proficiency Testing on Drugs of Abuse: One Years Experience in Spain. Clin Chem 1989; 35: 879–83
- Wilson J F, WilUams J, Walker G, et al. Performance of Techniques Used to Detect Drugs of Abuse in Urine: Study based on External Quality Assessment. Clin Chem 1991; 37: 442–7
- Beck O, Lafolie P, Hjemdahl P, Borg S, OdeUus G, Wirbing P. Detection of benzodiazepine intake in therapeutic doses by immunoanalysis of urine: Two techniques evaluated and modified to improved performance. CUn Chem 1992; 38: 271–5
- Hawks R F, Chiang C N. Urine testing for drugs of abuse. National Inst Drug Abuse Research Monograph 1986; 73: 1–122, Series
- Wu A HB, Wong S S, Johnson K G, Ballatore A, Sei-Fert W E, Jr. The conversion of ephedrine to metam-phetamine and metamphetamine-Uke compounds during and prior to gas chromatography /mass spec-trometric analysis of CB and HFB derivatives. Biol Mass Spectrom 1992; 21: 278–84