Parmar 1993.

Study characteristics
Methods	Q‐RCT, parallel design, 2‐armed trial
Participants	Total number of randomised participants: 80. No explanation about discrepancy in 24 missing participants, as sample drops from 80 to 56 at follow‐up Source population: single centre, UK Inclusion criteria: all participants had x‐ray and CT scans preoperatively; displaced intra‐articular fractures entered into trial Exclusion criteria: undisplaced and extra‐articular fractures were treated conservatively, bilateral fractures except when extra‐articular fracture on 1 side was of no clinical significance and allowed full weight‐bearing after initial bed rest, and those "who could not be randomised" (no reasons given) Overall baseline characteristics Bilateral fractures: 5 participants had sustained a minor extra‐articular fracture on 1 side that did not interfere with the management of the contralateral intra‐articular fracture. Bilateral fracture participants were recruited but excluded from 1‐year analysis. Baseline characteristics for surgical group Age, mean (range): 48.8 (20 to 79) years Sex (M/F): 21/4 Baseline characteristics for non‐surgical group Age, mean (range): 48.3 (20 to 72) years Sex (M/F): 27/4
Interventions	Surgical group Number randomised: unknown* Losses (with reasons): unknown Number analysed: 25 Treatment description: open lateral reduction and K‐wire fixation of the posterior subtalar joint. Postoperative immobilisation in a plaster cast for 6 weeks. All participants in both groups remained non‐weight‐bearing for 6 to 8 weeks, then gradual weight‐bearing started. Non‐surgical group Number randomised: unknown* Losses (with reasons): unknown Number analysed: 31 Treatment description: closed mobilisation of the hindfoot. Elevation and ice for 5 to 7 days, with movement encouraged as pain allowed, non‐weight‐bearing for 6 to 8 weeks. All participants in both groups remained non‐weight‐bearing for 6 to 8 weeks, then gradual weight‐bearing started. *80 participants randomised overall, but this is not described by group. No explanation about discrepancy in 24 missing participants, as sample drops from 80 to 56 at follow‐up
Outcomes	Timing of assessments: 12 and 24 months (main 1993 paper); mean follow‐up 23 months (surgical follow‐up: mean 25.3 months; conservative: 21.6 months); later publication of 15‐year outcomes on subset of 26/56 responding survivors (46%) (Ibrahim 2007) Outcomes reported in review: pain, employment, shoe wear, recreation level Other outcomes: use of analgesia, site/pattern of pain, walking difficulty, heel width, recovery plateau reached, compensation pending, no or mild problems, sural nerve symptoms. At 15 years: multiple outcomes including AOFAS Hindfoot scale, Calcaneal Fracture Scoring system and Foot Function Index and subtalar arthrodesis Note: we did not include 15‐year data for subtalar arthrodesis, as this information was available for only 26 of the original sample, and we judged that attrition was too high to provide reliable data
Notes	Study dates: participants recruited from 1985 and 1992 Funding sources: not reported Declarations of interest: not reported Notes: data in Parmar 1993 also reported for undisplaced fractures. Data difficult to interpret for some outcomes at 1 year, partly because data were presented as percentages. We attempted to contact the lead author on a later paper for more information (Ibrahim 2007), but the email address was no longer valid.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quasi‐randomised by year of birth, with odd years entering the operative group and even years the conservative group
Allocation concealment (selection bias)	High risk	Allocation predictable if year of birth is known
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	No details provided about blinding of outcome assessors at 1 to 2 years follow‐up and we therefore assumed no blinding took place.
Incomplete outcome data (attrition bias) All outcomes	High risk	Lack of detail about numbers randomised (n = 80) and data reported at 2 years (n = 56). Previous review contacted authors and were informed that 24 participants were excluded because follow‐up was less than 1 year (30%). Results presented as whole percentages ‐ these often do not correspond to whole numbers, indicating either errors in the calculation of percentages or different denominators.
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.
Other bias	Low risk	We identified no other sources of bias