2.2. Randomization and Masking
LIVER
Through a computer-generated centralized management program, all participants were randomized by a stratified computed randomization procedure to account for age, sex, and BMI to test group or control group at a ratio of 1 : 1 and were masked to the treatment assignment. The test group received pioglitazone-metformin combined treatment, and the control group received metformin treatment and matching placebo treatment. The electronic master randomization list was only accessible to the assigned randomization list managers, and study sites received sealed opaque envelopes for unblinding in cases of emergency. Enrollment was performed at the respective site. Randomization and assignment to the double-blind study drug were done by central pharmacy personnel, who had access to the computer-generated randomization scheme. The appearance, color, and smell of all simulated tablets are the same as the corresponding drugs. Liver fat content testing in all test centers is performed by fixed personnel, and all testing personnel have been uniformly trained to ensure the same measurement quality.