Zhu 2009.

Methods	RCT
Participants	90 participants divided into three groups. Adults > 40 yrs. Treatment naive Three treatment groups ‐ A) 100 U BTX, B) PD with 30 mm Rigifex balloon, C) PD followed by BTX injection 15 days later Baseline characteristics similar in the two relevant groups Outcomes based on single treatment
Interventions	Three treatment groups ‐ A) 100 U BTX, B) PD with 30 mm Rigifex balloon, C) PD followed by BTX injection 15 days later
Outcomes	Clinical assessment (mean symptoms score based on dysphagia for solids and liquids, active and passive regurgitation. and chest pain; each scored 0 to 3) and mean lower oesophageal sphincter pressure were assessed after therapy at 1 month, 6 months, 12 months, 18 months, and 24 months
Notes	No major complications reported ‐ significant bleeding requiring hospitalisation, oesophageal perforation, and aspiration 3 lost to follow up (one from BTX and 2 from PD group) ‐ excluded from analysis
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer generated random numbers
Allocation concealment (selection bias)	Low risk	Allocation concealed, randomisation occurred after enrolment. Patients blinded to therapy
Blinding (performance bias and detection bias) All outcomes	Low risk	Patients and assessors blinded to therapy
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Patients and assessors blinded to therapy
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Patients and assessors blinded to therapy
Incomplete outcome data (attrition bias) All outcomes	Low risk	3 lost to follow up