Joharchi 2019.

Study characteristics
Methods	Design: parallel Duration: 12 weeks Assessment: baseline, 4 weeks, 8 weeks, post‐intervention Country: Iran
Participants	Pain condition: diabetic peripheral neuropathy Population: type 2 diabetic adults aged ≥ 40 and ≤ 65 with diabetic peripheral neuropathic pain Minimum pain intensity: ≥ 40 on 0‐100 VAS Inclusion criteria Aged 40‐65 Diabetes duration ≥ 5 years Diabetic peripheral neuropathy diagnosis Diabetic peripheral neuropathy severity ≥ 40 on 100 VAS with a duration of ≥ 12 months Exclusion criteria Severe physical and mental health comorbidities Total participants randomised: 180 Age in years (mean): 54.48 Gender: 109/180 were female Pain duration in years (mean): 3.8
Interventions	Duloxetine 30‐60 mg n = 90 SNRI Flexible dose dependent upon efficacy and tolerability Mean dose: 42.5 mg/day Pregabalin 150‐300 mg n = 90 Anticonvulsant Flexible dose dependent upon efficacy and tolerability Mean dose: 235.5 mg/day
Outcomes	Pain intensity AEs Withdrawal
Missing data methods	Completer analysis
Funding source	Non‐pharmaceutical: part of a PhD project ‐ financially supported by “Research Department of theSchool of Medicine Shahid Beheshti University of Medical Sciences(SBUMS)” (Grant No 13/587).
Conflicts of interest	The authors declare that they have no COI.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomisation methods not specified: Just states "randomly divided into 2 groups"
Allocation concealment (selection bias)	Unclear risk	Allocation procedures not described
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Used "similar" capsules but participants in pregabalin arm took 2 capsules a day compared to 1 a day for duloxetine
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Self‐reported outcomes from blinded participants, unsure of blinding procedures
Incomplete outcome data (attrition bias) All outcomes	High risk	Higher attirition in duloxetine group than pregabalin, completer analysis only Attrition Total: 36/180 (20.0%) Duloxetine 30‐60 mg: 24/90 (26.7%) Pregabalin 150‐300 mg: 12/90 (13.3%)
Selective reporting (reporting bias)	Low risk	Protocol registered prospectively to study with outcome measures
Other bias	Low risk	No other sources of bias were identified.