Pandazi 2010.

Study characteristics
Methods	Study design: parallel‐group randomized controlled trial Sample size: 40 Country: Greece Setting: secondary care hospital Dates conducted: not reported Postoperative opioid used and delivery: morphine PCA Pain score collection: blinded anaesthetist Concurrent postoperative analgesics: none reported
Participants	Inclusion criteria Elective surgery for colorectal cancer ASA 1 or 2 Exclusion criteria Allergy to NSAIDs Peptic ulcer Coronary artery disease Severe cardiac insufficiency Renal insufficiency COPD IBD Use of analgesic medication the week before surgery
Interventions	Group PRE (20 participants): 40 mg IV parecoxib 30 minutes before surgery and 100 mL saline 30 minutes after incision. Then parecoxib 40 mg BD for three days Group POST (20 participants): 40 mg IV parecoxib 30 minutes after incision and 100 mL saline 30 minutes before surgery. Then parecoxib 40 mg BD for three days
Outcomes	Postoperative pain (0‐10 VRS at 1, 6, 18 and 24 hours) Morphine consumption (mg at 1, 6, 18 and 24 hours) Nausea and vomiting (24 hours) Cytokines (IL‐6, IL‐8, and TNF‐alpha at baseline, intraoperative and 24 hours) Pruritus and respiratory depression (24 hours)
Notes	Funding: not reported Declarations of interest: not reported Authors contacted: no Other: pain scores reported as median so used as means and IQR/1.35 to convert to SD. No events for pruritus or respiratory depression
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated. Quote "Computer generated randomization list run by the hospital pharmacist"
Allocation concealment (selection bias)	Low risk	Pharmacy‐controlled. Quote "Computer generated randomization list run by the hospital pharmacist"
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double‐dummy placebo. Quote "A trained nurse administered an intravenous (IV) solution of 100 ml normal saline with parecoxib 40 mg to group PRE (preincisional) and an IV solution of 100 ml normal saline to group POST (post‐incisional) 30 min before skin incision. The same nurse administered 100 ml normal saline with parecoxib 40 mg to group POST and 100 ml normal saline to group PRE 30 min after skin incision. The solutions were dispensed by the hospital pharmacist".
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinded. Quote "All participants in the study (nurse, surgeon, anesthesiologist, patients) were blinded to the perioperative intervention".
Incomplete outcome data (attrition bias) All outcomes	Low risk	Only one participant excluded, unlikely to cause bias
Selective reporting (reporting bias)	Unclear risk	24807/20‐12‐06 trial registration but unable to locate protocol
Other bias	Low risk	Similar baseline characteristics