Additional inclusion criteria for Stage II and eligibility:
Patients were eligible to be included in Stage II if they: ix)reported experiencing moderate to severe pain; x) had used strong opioid analgesics for at least one week to relieve pain associated with incurable malignancy (one-week prior use of opioid treatment is sufficient duration because it would represent established opioid treatment and most patients would have developed tolerance after one week, especially with multiple daily doses totalling > 60 mg of oral morphine or equivalent) and/or patient is on a low dose opioid regimen and still experiencing pain and is unable to increase the opioid dose due to poor tolerance as confirmed by the treating principal investigator; xi) reported pain severity greater than four on a 0-10 Numerical Pain Rating Scale (NPRS) assessment tool.