Williams 2013.

Methods	Randomised controlled trial Study period: April 2006 to May 2009
Participants	St Louis Children’s Hospital, St Louis, Missouri, USA 94 children with a radiologically confirmed distal radial buckle fracture Exclusion: skeletally mature, previous distal radial buckle fractures, or concurrent other fractures except for an ipsilateral ulnar buckle fracture. Patients with osteogenesis imperfecta or other metabolic bone diseases. Sex: 51 male (54% of 94) Age: median 9.5 years (splint); median 9 years (cast); range 2 to 16 years Fracture type: buckle fracture Assigned: 43 (splint)/ 51 (cast) Analysed: 43 (splint)/ 51 (cast)
Interventions	1. Prefabricated wrist splint. In the event that an appropriately‐sized, prefabricated cock‐up splint was not available, a custom splint was made from plaster. Children were advised to wear the splint as much as possible. However, parents were told that it was likely the child would remove the splint more frequently as pain improved. Trial registration indicates the Velcro volar splints were "Biomed Volar Splint" and that these were to be worn until follow‐up at 3 weeks 2. Short‐arm fibreglass cast with protective layers of stockinette and webril underneath. Children were given standard cast‐care instructions, such as keeping the cast dry and returning for any concerns with the cast Cast or splint application was performed or supervised by an attending physician or paediatric emergency medicine fellow in the paediatric emergency department. There were no stated limitations on activities for either group. Both groups were advised to follow up with the paediatric orthopaedic department in 3 weeks for a re‐evaluation
Outcomes	Length of follow‐up: 3 weeks; phone calls on day 1, 3, 7 and 21 and 21 day follow‐up visit Function (Peds QL questionnaire): primary outcome listed in the trial registration but not reported in full article. Satisfaction and convenience Pain Parental preference for same immobilisation device in future Resource utilisation (assistant required, median time for immobilisation, physician delay) Treatment concerns Number of times splint removed each day (at 1 and 3 weeks)
Funding and declarations of interest	Funding source: not stated Declarations of interest: reported, none
Notes	JE sent Williams an email 03.08.17 checking link with trial registration (NCT01010347); and depending on the answer: his plans for reporting either the listed primary outcome (Peds QL) or the other trial. Also checks on loss to follow‐up at 3 weeks, how many children were still using their splint at 3 weeks and how many children in the cast group had their cast removed at 3 weeks. No response received.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: “The randomisation sequence was computer‐generated with a block size of 10 ..."
Allocation concealment (selection bias)	Unclear risk	Quote: “The randomisation sequence was computer‐generated with a block size of 10, and sealed, opaque envelopes were included in each study packet.” No mention of sequential numbering
Blinding of participants and personnel (performance bias) Subjective outcomes	High risk	Blinding not feasible
Blinding of participants and personnel (performance bias) Objective outcomes	High risk	Blinding not feasible
Blinding of outcome assessment (detection bias) Subjective outcomes	High risk	No blinding
Blinding of outcome assessment (detection bias) Objective outcomes	High risk	No blinding reported
Incomplete outcome data (attrition bias) Subjective outcomes	Low risk	No loss to follow‐up reported
Incomplete outcome data (attrition bias) Objective outcomes	Low risk	No loss to follow‐up reported
Selective reporting (reporting bias)	High risk	Retrospective trial registration and no published protocol. No participant‐reported measures of function, but daily function assessed with the “Peds QL” questionnaire was the primary outcome listed in the trial registration. Outcomes not measured until or after cast and splint removal; timing of these not reported. Some data discrepancies
Other bias: major imbalance in baseline characteristics	Low risk	Quote: “There were no significant differences for gender, age, ethnicity, right‐hand dominance, fracture location, or history of prior cast or splint”. Baseline preferences favoured splint use but this is already considered under blinding
Other bias: performance bias	Unclear risk	Quote: “The application of the cast or splint was performed or supervised by an attending physician or pediatric emergency medicine fellow in the pediatric ED.” Level of training of physician was recorded but not reported Quote: “At the 3‐week follow‐up visit with orthopedics, a cast technician or nurse practitioner assessed the integrity of the immobilization technique and recorded the findings on a data sheet.” No information on timing of removal of cast
Other bias	Unclear risk	Only 3 weeks follow‐up

ADL: activities of daily living; A&E: Accident and Emergency department; ASK: Activities Scale for Kids; ASP‐P: Activities Scale for Kids – Performance (also written as ASKp); N/A: not applicable or available; POP: plaster of Paris; VAS: visual analogue score