Randomization and blinding
RECRUITMENT
The participants were randomly allocated to the four intervention arms upon successful completion of the baseline measurements. An independent statistician (author R.C.) prepared a computer-generated randomization schedule in a ratio of 1:1:1:1, stratified by sex. To ensure concealment, the (permuted) block sizes were not disclosed. The schedule was forwarded to a secretary who was not involved in any study procedures and stored on a password-protected computer. Sequentially numbered, opaque, sealed envelopes were prepared and stored in a locked cabinet before commencing the recruitment. The envelopes were lined with aluminum foil to render the envelope impermeable to intense light. Following the conclusion of the hyperglycemic clamp, the appropriate envelope was opened by a study nurse, and the participant was informed about the allocation stated on the card inside the envelope. The participant received the allocation in a closed room. As such, the participants were blinded for treatment allocation until after the completion of the hyperglycemic clamp. Following the baseline assessment, blinding of the participants was no longer possible. Both study personnel involved with the data collection and the study endocrinologist managing pharmacological treatment and safety were blinded to allocation. The clinical results used for pharmacological management and safety assessment were presented to the endocrinologist by the study nurse without disclosing participant allocation.