De Conno 1995.

Methods	Design: randomised, double blind (double dummy), two‐period cross‐over study. Assessments at 10, 20, 30, 40, 60, 90, 120, 180 and 240 mins daily Duration: 2 x 2 days Setting: outpatients
Participants	Advanced or metastatic cancer with PI > 30/100 mm at baseline, opioid‐naive N = 34 M 23, F 11 Mean age 59 (SD 8.8; range 38 to 70)
Interventions	Oral morphine 10 mg Rectal morphine 10 mg Single dose administered on each of two days then crossover to other treatment. Use of NSAIDs allowed for first day
Outcomes	PI: VAS Nausea and sedation: VAS Number of vomiting episodes Time to pain relief
Notes	Oxford Quality Score: R = 1, DB = 2, W = 0. Total = 3/5
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomly allocated ... according to a predetermined allocation sequence". Method used to generate sequence not clearly stated
Allocation concealment (selection bias)	Unclear risk	Method not described
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"double blind double dummy technique"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"double blind double dummy technique"
Incomplete adverse event outcome data‐ patient level	Low risk	>90% participants included
Selective reporting bias for adverse events	High risk	Only nausea, vomiting & sedation reported
Size	High risk	< 50 participants per treatment arm