Inoue 2001.

Methods	Location of trial: Japan. Number of centres: 1. Funding: not stated. Trial ID: not stated.
Participants	Inclusion criteria: patients with early mobile tongue cancer, T1‐2, N0 which could be treated with a single plane implantation, localisation of tumour at lateral border of the tongue, and tumour thickness less that 10 mm, performance status 0‐3. Exclusion criteria: any severe concurrent disease. Recruitment period: April 1992 to October 1996. OC: 59/59 (100%). Number randomised: 59. Number analysed: 51.
Interventions	Low dose rate interstitial radiotherapy versus high dose rate interstitial radiotherapy Low dose (n = 26): 0.30 to 0.93 Gy/h to total dose of 65‐75 Gy (median 70 Gy) over 75 to 217 hours (median 117 hours). High dose (n = 30): 0.99 to 4.1 Gy/min to total dose of 60 Gy in 10 fractions over 6‐9 days (median 7 days) with 2 fractions per day and interfraction interval of > 6 hours.
Outcomes	Primary: locoregional control. Secondary: cause specific survival. Duration of follow‐up: minimum of 46 months (median duration of follow‐up is 85 and 78 months in the low dose and high dose groups respectively).
Notes	HR data taken from Kaplan‐Meier graphs (no numbers at risk).
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Low risk	"Randomly allocated into LDR & HDR groups according to Peto's balanced randomisation list."
Allocation concealment?	Unclear risk	Not mentioned.
Blinding ‐ Outcome Assessors	High risk	Not mentioned.
Incomplete outcome data addressed?	Unclear risk	8 patients were excluded; 3 (10%) from low dose rate and 5 (20%) from high dose rate but reasons are not given for each treatment group. This is a possible cause of bias.
Free of selective reporting?	Unclear risk	Some important outcomes, locoregional control, survival and cause specific survival are reported but there are no data on toxicity.
Free of other bias?	Unclear risk	At baseline there is some difference between groups with regard to tumour thickness. Low dose rate group has more medium thickness tumours and high dose rate more very thick tumours. Tumour thickness is likely to be an important prognostic factor linked to outcome.