Randomization and blinding
The eligible patients were randomly assigned into 1:1 low-dose and standard-dose groups through the block-randomization technique (block size: 8). The randomized computer-generated numbers were placed within sequentially-numbered, opaque, sealed envelopes. Before the biopsy, envelopes were opened by a member of the Science and Education department without a defined role in the trial. This RCT was single-blinded for the patients.