Nouraei 2011.

Study characteristics
Methods	RCT, parallel design, 2‐armed trial
Participants	Total number of randomised participants: 72 Source population: single centre, Iran Inclusion criteria: displaced intra‐articular fracture. States in text that 11 participants had bilateral fracture, but no description about allocation to intervention Exclusion criteria: states that "reasons that patients were not selected for surgery were as follows: participant disagreement with surgery, open fractures (not suitable for open reduction internal fixation), combined injuries (head trauma, cardiovascular disorders, severe osteoporosis...), also severe comminution" Overall baseline characteristics Age, mean (distribution type not specified): 49 (21 to 84) years Sex (M/F): not reported Bilateral fracture: 11 participants, no information provided about allocated intervention Baseline characteristics for surgical group (for participants included in analysis) Age, mean (SD): 46 (± 8.2) years Type of fracture (Sanders I/II/III/IV): 1/20/8/2 Baseline characteristics for non‐surgical group (for participants included in analysis) Age, mean (SD): 52 (± 12.3) years Type of fracture (Sanders I/II/III/IV): 5/8/8/5
Interventions	Surgical group Number randomised: unknown* Losses (with reasons): unknown Number analysed: 31 Treatment description: open reduction and internal fixation with reconstruction plate and screw fixation. Period of non‐weight‐bearing for 6 to 10 weeks after surgery. States that 2 different surgical procedures were used: 17 participants had Essex‐Lopresti technique (uses fluoroscopy x‐ray, closed reduction, internal fixation with pins, and cast immobilisation), and 14 participants had open reduction with lateral calcaneal approach and fixation with a reconstruction plate. The reason for these different approaches is not described. Non‐surgical group Number randomised: unknown* Losses (with reasons): unknown Number analysed: 30 Treatment description: splinting, ice pack, elevation, closed reduction, and cast immobilisation. Ambulation after 3 days with crutches. Cast removed after 6 weeks. *Total number randomised is 72. However, 11 participants were lost to follow‐up, and the groups to which they originally had been allocated are unknown.
Outcomes	Timing of assessments: clinical examination at 2 weeks, 1, 3, 6 months, and 1 year. Questionnaire follow‐up at 6 months Outcomes reported in this review: pain on walking (n,%), ability to wear footwear, complications. Study authors state that function was recorded using Kerr‐Atkins score, but results for this outcome were not reported. Other outcomes: swelling, limitation of activity, RoM, osteoarthritis, patient satisfaction
Notes	Study dates: December 1998 and January 2009 Funding sources: not reported Declarations of interest: "authors have no conflict of interests" Notes: study authors were contacted for further information, but no reply was received
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	No details provided. States that "consecutive participants were randomly allocated to surgical and non surgical groups". We noted that participants were excluded from the surgical group if they had comminuted fractures, but these fracture types were not excluded from the non‐surgical group (4 of 30 participants in the non‐surgical group had comminuted fractures). We judged this to indicate possible manipulation of the randomisation method.
Allocation concealment (selection bias)	Unclear risk	No details provided
Blinding of participants and personnel (performance bias) All outcomes	High risk	Due to nature of intervention, treating surgeons and participants were not blinded
Blinding of outcome assessment (detection bias) All outcomes	High risk	Participant‐reported outcomes were collected by questionnaire at 6 months, and participants were aware of their treatment allocation. No information given on clinical outcome data collection or interpretation of x‐rays, and we assumed that no blinding took place
Incomplete outcome data (attrition bias) All outcomes	High risk	11 (15%) participants dropped after hospital discharge but these are reported as exclusions not as losses to follow‐up. Actual number randomised to each intervention arm is not reported.
Selective reporting (reporting bias)	Unclear risk	No protocol or clinical trials registration. It is not feasible to effectively assess risk of selective reporting bias without these documents. Patient satisfaction is included as an outcome in the Methods section but is not reported in the Results section of the study report.
Other bias	Low risk	We identified no other sources of bias