Schulte 2014.

Methods	Randomised controlled trial Study period: June 2008 to September 2009
Participants	Department of Emergency Medicine, University Children’s Hospital, Zurich, Switzerland 40 children with displaced distal radius fracture (out of 100 children with displaced closed forearm fractures needing reduction) Inclusion: Children younger than 16 years presenting to the emergency department with a closed fracture of the forearm needing reduction; Informed consent obtained Exclusion: Pre‐existing ailments such as skin infection of the affected limb, buckle fractures, compound fractures, fractures needing open reduction or wire fixation, and pathologic fractures Sex: 28 male (70% out of 40) Age: mean 9.1 years (for whole study population) Fracture type: distal forearm (40, of which 12 involved growth plate); number of both‐bone fractures not known but 52 of the 100 children in study had both‐bone fractures Assigned: 17 (split) / 23 (closed) Analysed: 17 (split) / 23 (closed)
Interventions	Standardised closed reduction in ED (performed or supervised by senior emergency physician) 1. Split circumferential synthetic semi‐rigid above‐elbow cast. According to the protocol, the casts were split using cast scissors or cast saw or both; time of sedation extended for this group 2. Closed circumferential synthetic semi‐rigid above‐elbow cast Participants had casts on for 4 weeks. Radiological diagnosis was confirmed with a radiologist within 24 hours. All cast applications and manipulations were performed by specialised casting nurses. All participants and their parents were given standardised post‐op instructions and analgesia. Cast removal was performed with a cast scissor or saw or both at the discretion of the casting nurse
Outcomes	Length of follow‐up: 4 or 6 weeks (or 3 months if delayed union); also on day 1, 5 and 10 Function not reported Fracture redisplacement requiring surgery Secondary splitting due to reversible lymphoedema Cast‐related soft tissue problems: compartment syndrome, neurovascular compromise, saw burns, skin breakdown (< 2 cm2)
Funding and declarations of interest	Funding source: not stated Declarations of interest: reported, none
Notes	JE emailed Daniel Garcia 21.06.17 for additional data. Garcia replied 27.06.17 with data. Upon a further request by JE for data on relevant secondary displacement necessitating surgical treatment for split and closed cast, Garcia confirmed on 09.08.17 that they had "3 secondary surgeries regarding distal fractures in the closed cast group and 2 in the split cast group".
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The sequence was generated by a computer in blocks of 10
Allocation concealment (selection bias)	Unclear risk	Quote: “Randomization was performed by sealed opaque envelope” There is no mention of sequential numbering of the envelopes
Blinding of participants and personnel (performance bias) Objective outcomes	High risk	Quote: "Apart from the radiologist assessing the fracture alignment, none of the other researchers, clinicians, patients or families were blinded to the intervention"
Blinding of outcome assessment (detection bias) Objective outcomes	High risk	Quote: "Apart from the radiologist assessing the fracture alignment, none of the other researchers, clinicians, patients or families were blinded to the intervention" Fracture alignment was measured by a blinded radiologist
Incomplete outcome data (attrition bias) Objective outcomes	Low risk	None lost to follow‐up
Selective reporting (reporting bias)	Unclear risk	No trial registration or published/protocol. Separate data for DRF obtained from authors. However, no reporting of child function or recovery
Other bias: major imbalance in baseline characteristics	Unclear risk	Quote: “Demographic and fracture characteristics were similar in both groups” (Table 1) However, little data for distal radius fractures, with an imbalance between groups in the sexes: 17/17 (100%) male in the split cast group and 11/23 (48%) in the closed cast group
Other bias: performance bias	Unclear risk	Quote: “All casts applications and manipulations were performed by specialized casting nurses.” Quote: “Cast removal was performed with a cast scissor and/or saw at the discretion of the casting nurse.” No data on cast index. Insufficient information reported
Other bias	Low risk	None detected