Rauch 2011.

Study characteristics
Methods	Non‐blinded, parallel‐group randomised controlled trial with 2 weeks duration of treatment and a 6‐month duration of follow‐up
Participants	Setting: multicentre trial, USA, December 2004 to October 2009 Sample size: Number randomised: 255 Number completed: 221 Primary/secondary therapy: primary therapy Participant (baseline) characteristics: age/sex (male, female)/baseline hearing loss at start of therapy/start of treatment/baseline WRS: Group I (intratympanic): 51.3 y (95% CI 48.8 to 53.9)/m:f = 1.5:1/86.4 dB HL (95% CI 82.8 to 90.0)/7.0 d (95% CI 6.4 to 7.6)/15.9% (95% CI 12.0 to 19.7) Group II (systemic): 50.4 y (95% CI 47.9 to 52.8)/m:f = 1.6:1/86.7 dB HL (95% CI 82.9 to 90.6)/6.7 d (95% CI 6.1 to 7.4)/14.0% (95% CI 10.3 to 17.7) Inclusion criteria: age > 18 years, unilateral SNHL that developed within 72 hours and was present for < 14 days, PTA > 50 dB and the affected ear must have been > 30 dB worse than the contralateral ear in at least 1 of the 4 PTA frequencies, to the best of the participant’s knowledge, hearing must have been symmetric prior to onset of SSNHL Exclusion criteria: structural or retrocochlear pathology, participants were neither known nor expected to have had any preceding otolaryngological encounters
Interventions	General comparison: intratympanic versus systemic corticosteroid therapy Intervention group (n = 129*): "intratympanic therapy": intratympanic 40 mg/mL of methylprednisolone, 1 mL, 1x every 3 to 4 days over 2 weeks Comparator group (n = 121*): "systemic therapy": oral 60 mg/d for 14 days, followed by a 5‐day taper (50 mg, 40 mg, 30 mg, 20 mg and to 10 mg), for a total of 19 days Use of additional interventions (common to both treatment arms): none *intention‐to‐treat analysis
Outcomes	Primary outcome measure: Change in hearing threshold with pure tone audiometry (at 2‐month follow‐up) Secondary outcomes: Change in hearing threshold at 6‐month follow‐up and change in hearing threshold with speech audiometry Difference in PTA between affected and unaffected ears Adverse events Primary endpoint for hearing threshold evaluation: 60 days Used PTA: 4PTA (0.5, 1, 2, 4 kHz)
Funding sources	Quote: "This study was funded by grant U01‐DC006296 from the National Institute on Deafness and Communication Disorders (USA)."
Declarations of interest	Quote: "All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Harris reported that he has a financial interest in Otonomy Inc. Drs Rauch, Carey, Gantz, and Harris reported that they have served as paid consultants of Otonomy, and Drs Rauch, Gantz, and Linstrom reported that they have been investigators in a clinical trial supported by Otonomy Inc; otherwise, no other conflicts were reported."
Notes	This study is registered in clinicaltrials.gov (NCT00097448)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Permuted block randomization stratified by study site … was accomplished by telephone call to the data coordinating center." "The randomization codes were computer generated … Only personnel at the data coordinating center had access to the codes"
Allocation concealment (selection bias)	Low risk	Quote: "Permuted block randomization stratified by study site … was accomplished by telephone call to the data coordinating center." "The randomization codes were computer generated … Only personnel at the data coordinating center had access to the codes"
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "The participants and treating physicians were not blinded to treatment."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Audiologists were blinded to treatment".
Incomplete outcome data (attrition bias) All outcomes	Low risk	Low missing outcome data (< 5%).
Selective reporting (reporting bias)	Low risk	All pre‐specified endpoint measurements of outcome parameters addressed by the review are reported.
Other bias	Low risk	No indication of other bias.