Hanks 1995.

Methods	Design: randomised, double blind (double dummy), two phase cross‐over study. Assessments x 4 on last day of each treatment phase Duration: 2 x 3 days Setting:
Participants	Advanced malignant disease with pain requiring at least 400 mg morphine/day N = 25 (19 completed) M 11, F 14 Mean age 56 years (range 35 ‐ 69)
Interventions	Mm/r 100 mg Mm/r 200 mg Exact dose made up with standard CR morphine tablets (30 ‐ 100 mg), but dose remained constant throughout study Rescue medication: morphine elixir ≤ 1/6 total daily dose
Outcomes	PI: VAS Symptom score: categorical 4‐point. Scores taken x 4 on days 3 and 6 Use of rescue medication Morphine plasma concentrations in 4 participants
Notes	Oxford Quality Score: R = 1, DB = 2, W = 1. Total = 4/5
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"patients were randomised". 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 crossover ...." "identical tablets"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"double blind double dummy crossover ...." "identical tablets"
Incomplete adverse event outcome data‐ patient level	Low risk	> 90% of participants included
Selective reporting bias for adverse events	High risk	Selective reporting of AEs
Size	High risk	< 50 participants per treatment arm