Wikström 2005a.

Methods	RCT Placebo‐controlled Parallel‐group design
Participants	Pruritus: UP          Description: participants with ESRD on haemodialysis Number of participants randomised: 51 Nalfurafine: 26 Placebo: 25 Number of participants evaluable: 48 Withdrawals/dropouts: Nalfurafine: 2 Placebo: 1 Reason for dropout: Nalfurafine: moderate nausea and vomiting (n = 1), reason for second participant not provided Placebo: reason not provided Age (years): no information Sex (male/female): no information Underlying disease(s): ESRD Participant pool: multicentre Setting: no information Haemodialysis: no information Baseline pruritus assessment: yes Duration/severity of pruritus: severe, uncontrolled pruritus secondary to ESRD; at least 3 "worst itching" VAS measurements during run‐in period of > 50 mm and average worst itching > 25 mm Baseline parameters: Pruritus relief (measured by VAS 100 mm): (mean ± SD) Nalfurafine: 65.3 (± 15.2) Placebo: 65.3 (± 15.0)
Interventions	Intervention 1: nalfurafine (5 µg 3x/week immediately after their haemodialysis session) Intervention 2: placebo Additional medication: before the run‐in period all antipruritic medications, except for topical neutral agents, were discontinued for at least 7 days Route of administration: intravenous Duration of treatment: 4 weeks (1 week run‐in period ‐ 4 weeks nalfurafine/placebo) Follow‐up: 2 weeks after the administration of the final dose
Outcomes	Pruritus assessment: VAS 100 mm Adverse events
Notes	Not clear who conducted the study; not clear if and where study was published; 17 (65%) of 26 participants had adverse drug events in the nalfurafine group, but only 15 were described
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method not stated "Seventy‐nine patients were randomly assigned in this study."
Allocation concealment (selection bias)	Unclear risk	No information provided
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Unclear who was blinded
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No information provided
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Substantial missing outcome data; number of participants included unclear
Selective reporting (reporting bias)	Unclear risk	Conflicting data (number of participants included); combined results from study Wikström 2005b
Size of study (possible biases confounded by small size)	High risk	Number of participants randomised: 51
Other bias	Unclear risk	Missing participant characteristics; Bergstrom effect; assessment of compliance not stated