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2. US Food and Drug Administration. Title 21 code of federal regulations (21 CFR part 11): electronic records; electronic signatures. URL: www.fda.gov/ora/compliance_ref/part11/.
3. US Food and Drug Administration. Guidance for industry. E6 good clinical practice: consolidated guidance. URL: www.fda.gov/cder/guidance/959fnl.pdf.
4. World Health Organization. Handbook for good clinical research practice (GPC): guidance for implementation. URL: www.ori.dhhs.gov/documents/WHOHandbookonGCP04-06.pdf.
5. Clinical Trial Registration: A Statement from the International Committee of Medical Journal Editors