1. A Proposed Taxonomy of Terms to Guide the Clinical Trial Recruitment Process 
Neil A. Hagen, MD, FRCPC, Jackson S. Wu, MD, FRCPC, Carla R. Stiles, BN 
Journal of Pain and Symptom Management 
Volume 40, Issue 1, Pages (July 2010)
DOI: /j.jpainsymman
Copyright © 2010 U.S. Cancer Pain Relief Committee Terms and Conditions

2. Fig. 1
This trial tested a classification system tool. This is a noninterventional trial, and no consent was required as every patient admitted was assessed by the clinician who then completed the tool as standard assessment procedure. NNA=1.2.
Journal of Pain and Symptom Management  , DOI: ( /j.jpainsymman )
Copyright © 2010 U.S. Cancer Pain Relief Committee Terms and Conditions

3. Fig. 2
This trial involved the validation of a tool when compared with already established tools. This is a noninterventional trial that required informed consent. NNA=4.4.
Journal of Pain and Symptom Management  , DOI: ( /j.jpainsymman )
Copyright © 2010 U.S. Cancer Pain Relief Committee Terms and Conditions

4. Fig. 3
This was an open-label interventional trial investigating a well-known opioid for pain using a novel route of administration. Informed consent was required. Follow-up and frequent monitoring were parts of the protocol. NNA=250.
Journal of Pain and Symptom Management  , DOI: ( /j.jpainsymman )
Copyright © 2010 U.S. Cancer Pain Relief Committee Terms and Conditions

5. Fig. 4
This randomized double-blind trial investigated a novel analgesic, which involved a placebo control. Consent was required; rigorous documentation and follow-up were parts of the protocol. NNA=83.
Journal of Pain and Symptom Management  , DOI: ( /j.jpainsymman )
Copyright © 2010 U.S. Cancer Pain Relief Committee Terms and Conditions