Riest 2006.

Study characteristics
Methods	Study design: parallel‐group randomized controlled trial Sample size: 360 Country: Germany Setting: secondary care hospital Dates conducted: not reported Postoperative opioid used and delivery: morphine PCA Pain score collection: not reported Concurrent postoperative analgesics: none reported
Participants	Inclusion criteria Spinal, breast and orthopaedic surgery Aged 18‐88 years old General anaesthesia Exclusion criteria Mental or physical inability to handle a PCA ASA > 3 Opioid abuse Renal disease
Interventions	Group Perioperative (180 participants): rofecoxib 50 mg preoperatively and on postoperative days 1–3 Group Postoperative (180 participants): placebo preoperatively and rofecoxib on postoperative days 1–3
Outcomes	Postoperative pain (0‐4 scale at 12, 24, 48 and 72 hours postoperatively) Morphine consumption (mg at 12, 24, 48 and 72 hours postoperatively) Opioid adverse events (0‐4 scale at 12, 24, 48 and 72 hours postoperatively) Patient satisfaction (0‐4 scale at 12, 24, 48 and 72 hours postoperatively)
Notes	Funding: "This work was supported financially by MSD, Germany. MSD did not participate in either generations of hypothesis, data collection, analysis or writing" up the manuscript. Declarations of interest: as above Authors contacted: no Other: unable to include pain, opioid adverse events and patient satisfaction due to 0‐4 scale. Although multiple participant exclusions, data table for morphine consumption stated data from 540 patients.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated. Quote: "Randomization of study medications was performed by the hospital’s pharmacy using a computer generated random list".
Allocation concealment (selection bias)	Low risk	Pharmacy‐controlled. Quote: "Randomization of study medications was performed by the hospital’s pharmacy using a computer generated random list".
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Blinded. Quote: "To ensure blinding the study drugs were delivered as coated tablets in blister packages not allowing identification of content".
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Likely blinded from above information
Incomplete outcome data (attrition bias) All outcomes	High risk	90 patients excluded before outcome assessment. Quote: "We secondarily excluded 90 of the 630 patients before assessment of the primary criteria for to the following reasons: cancellation of surgery after the first dose of the study medication, administration of NSAIDs, steroids or opioids other than morphine during the study period, patients’ desire to be excluded from the study before assessment of the main outcome criteria (24 h after skin closure), patients’ discharge before assessment of main criteria, and sedation for mechanical ventilation at time of assessment of the main criteria".
Selective reporting (reporting bias)	Unclear risk	No protocol
Other bias	Unclear risk	No baseline characteristics. Industry funded but stated no involvement