Randomisation
The Newcastle Clinical Trials Unit Randomisation Service, an in-house bespoke internet based system, performed randomisation centrally using permuted random blocks of variable length. All allocations were generated by an automated process within the system. Participants were randomised 1:1 to receive either surgical intervention or medical management, stratified by sex and baseline severity of symptoms according to scores on the NOSE scale: 30-50 (moderate), 55-75 (severe), 80-100 (extreme).