Alali 2014.

Methods	Location: Syria Number of centres: 1. University of Damascus Recruitment period: not specified Funding source: not specified Trial design: parallel group RCT
Participants	Inclusion criteria: Class II/1 malocclusion with (overjet > 4 mm); mild to moderate skeletal Class II (ANB > 4° and APg/NL < 80°) with retrognathic mandible (SNB < 76°); the Fishman method was used to assess the hand‐wrist radiographs, and only patients in the pubertal growth spurt peak, which occurs between stages 4 and 7 at the beginning of the treatment/observation period, were invited. Exclusion criteria: none stated Age at baseline: mean age 13.2 years (SD 0.9) for Group 1 and 12.5 (SD 2.1) years for group 2 Number randomised: 43 Number evaluated: 38
Interventions	Gp 1 (n = 21): fixed lingual mandibular growth modificator Gp 2 (n = 17): control ‐ no or delayed treatment
Outcomes	Multiple cephalometric variables
Notes	Duration of randomised treatment (months): Gp 1 and Gp 2 = 8 months Sample size calculation: "Clinical and statistical significance in mandibular length change was defined, in the literature, as at least a +2‐mm difference between Class II treated and untreated groups. Based on that difference and standard deviation from previous investigations, a power analysis determined that, for a two‐sided 5% significance level and a power of 80%, a sample size of 16 per group would be required. Accordingly, assignment continued until 25 patients had enrolled in the treatment group to compensate for any unexpected dropouts. In the control group, the enrollment continued until the minimum number of patients required to satisfy the statistical power was reached."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"All subjects were randomized by the author at the beginning of the study to either the treatment or control group."
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"Cephalograms were digitized on screen and analyzed in a blind manner by the same orthodontist using cephalometric software."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	FLMGM group ‒ recruited 25, analysed 21 (loss 16%) Control group ‒ recruited 18, analysed 17 (loss 5%) Reasons for discontinuation: FLMGM group ‒ unable to return for final records because of change of residence (n = 4) Control group ‒ unable to return for final records because of change of residence (n = 1)
Selective reporting (reporting bias)	Low risk	All variables reported
Other bias	Low risk	No other sources of bias identified