Two RCTs were identified in which the abuse potential of tramadol was compared to another opioid analgesic. The results of one RCT were inconclusive given that no instances of abuse were identified. The other RCT suggested the abuse potential of tramadol was lower than hydrocodone-containing analgesics in patients with NCP and similar to that of NSAIDs. However, this study had limitations which could potentially affect the validity of the study’s findings. Further, both studies excluded patients who were at risk of abusing the study medications. While this exclusion criterion was based upon the investigators’ subjective assessment, it appeared that those patients who were at risk of becoming addicted to the study medication were screened out. Thus, based upon the available RCTs, it is not clear whether tramadol has a lower addiction risk than other opioid analgesics. As such, there is a lack of high quality evidence upon which to base formulary decisions about tramadol if such decisions were to be based upon its addiction risk profile relative to other opioid analgesics.