Leung 2004.

Methods	Quasi‐randomised, placebo‐controlled study
Participants	Setting: Chinese University of Hong Kong, China. Size: a total of 30 fractures in 28 patients. The test group had 16 fractures in 15 patients and the control group had 14 fractures in 13 patients. Baseline characteristics: mean (range) age 35.3 years (22 to 61), 25 males and 3 females. Inclusion: patients with open or comminuted tibial fractures. Exclusion: simple fractures, fractures of sites other than the tibia.
Interventions	Patients with closed fractures or Gustillo grade 1 or 2 open fractures in the diaphysis underwent fixation with reamed, locked intramedullary nail. Participants with fractures in the metaphysis or Gustillo grade 3 open fractures were treated with an external fixator. All open fractures were treated with emergency debridement and delayed closure. Test: LIPUS machine was given to the patients as soon as the soft tissues were closed. The ultrasound signal was composed of a 200 µs burst of 1.5 MHz sine waves, with a repetition rate of 1 kHz and a spatial average intensity of 30 mW/cm² and was given for 20 minutes a day, for 90 days using coupling gel applied directly over the fracture site. Control: a sham device that was externally identical to the LIPUS machine was given to the participants as soon as the soft tissues were closed.
Outcomes	End point was combined clinical and radiographic union. Clinical union was defined as full painless weight bearing. Radiographic union was defined as 3 out of 4 cortices were bridged with bone on plain orthogonal radiograph. Follow‐up times were every 3 weeks for the first 3 months, every 6 weeks for the following 3 months and every 8 weeks for the last 6 months. The radiographs were assessed by 3 independent surgeons and a mean time of union was used. Primary: time to union. Secondary: bone mineral density and plasma bone specific alkaline phosphatase, adverse events.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quote: "...assigned...according to the sequence of admission". Comments: Quasi‐randomised.
Allocation concealment (selection bias)	High risk	Quote: "...assigned...according to the sequence of admission". Comments: No list provided. Quasi‐randomised.
Blinding (performance bias and detection bias) Objective measures	High risk	Quote: "Control group were given a dummy machine". Comments: Efforts were made to blind the patients, but the assessors were not blind as the machines were not identical and the patients were quasi‐randomly allocated.
Incomplete outcome data (attrition bias) Objective measures	Low risk	The complete dataset was presented.
Selective reporting (reporting bias)	Unclear risk	No protocol available.
Other bias	High risk	Quote: "Four patients had segmental fractures..." Some participants had two fractures, which may have been randomised independently. No statistical adjustments were reported to allow for this
Selection bias (imbalance in baseline characteristics)	Unclear risk	Age, gender and smoking status not separately reported.