Inclusion and exclusion criteria
This study used the following inclusion criteria: (i) pathologic
diagnosis of malignant solid tumours with bone metastasis confirmed
by imaging [radiography, computed tomography (CT),
or magnetic resonance imaging (MRI)]; (ii) bone metastasisrelated
pain rated at ‡4 on an 11-point numeric rating scale
(NRS) (0 = no pain to 10 = worst pain imaginable); (iii) having
undergone titration and receiving treatment with controlledrelease
morphine or transdermal fentanyl patches (the two most
frequently used controlled-release opioids in China) for
‡1 week; (iv) conscious mental status and ability to take oral
tablets; and (v) at least 18 years of age.
The study used the following exclusion criteria: (i) having
received chemotherapy, radiotherapy, or endocrine or monoamine
oxidase-inhibitor therapy within 30 days before the
beginning of the study or during the study period; (ii) alcohol
abuse or severe hepatic disease; and (iii) having received NSAIDs
or paracetamol combinations.