McIlwain 2005.

Methods	RCT with case series open‐label continuation Duration: 3‐week RCT plus 12 month open‐label continuation; total 12.7 months
Participants	N = 491 enrolled in RCT, N = 153 enrolled in open‐label continuation Primary condition: Osteoarthritis of hip or knee Baseline pain score: 52.1 (SD 23)/100 VAS Time since onset: Mean duration range among the randomized groups 9.1 to 10.3 years Mean age: 60 (SD 10) years Female: 62% Previous opioid analgesics: Not reported, but to meet inclusion criteria patients must have had previous unsuccessful treatment with an opioid, NSAID, or Cox‐2 inhibitor for at least 75 of 90 days prior to enrolment
Interventions	Oral extended‐release morphine Initial dose: 40 mg/day Titrated up to 80 mg/day. Doses divided. Supplemental analgesia: All analgesics were discontinued in washout phase prior to randomization for RCT. For open‐label continuation, NSAIDS (50.3% of patients), other analgesics and antipyretics (44.4%), antidepressants (34.0%), and antipsychotics (30.7%) were taken.
Outcomes	Discontinuation due to adverse events Adverse events Discontinuation due to insufficient pain relief
Notes	Continuation of: Matsumoto AK, Babul N, Ahdieh, H. Oxymorphone extended‐release tablets relieve moderate to severe pain and improve physical function in osteoarthritis: Results of a randomized, double‐blind, placebo‐and active‐controlled Phase III trial. Pain Medicine 2005;6(5):357‐66.
Risk of bias
Bias	Authors' judgement	Support for judgement
Comparability of patients at baseline and follow‐up (continuous data) All outcomes	High risk	Due to attrition
Selection method random or consecutive	Unclear risk	Not reported
Prospective	Low risk	Prospective
Free from confounding treatment(s)	High risk	Concominant drugs allowed for extension
Patient compliance monitored and reported at at least 85%?	Unclear risk	Not reported
Attrition and right censoring less than 15% (continuous data) All outcomes	High risk	Greater attrition
Funding from a source without financial conflict of interest?	High risk	Funded by Endo Pharmaceuticals and Penwest Pharmaceuticals