Randomization, participant grouping and educator assigning
RECRUITMENT
We assigned women to study groups by tossing a coin (heads for the teach-back group and tails for the control group). The women were informed about the purpose and main topics of the education sessions, but they were not aware of the forms and techniques used in the trial, nor were they aware if they were assigned to the teach-back group or control group. For the first education session, the women were grouped based on the time of their recruitment, i.e., being the first recruited, being the first grouped and being the first to receive education; for the second education session, the women were grouped based on the time of their discharge, i.e., being the first discharged, being the first grouped and being the first to receive education. The educators were numbered from 1 to 8 according to their work shifts and were assigned to education sessions in sequence and cycle. For the third education session, the educators were assigned to contact women according to their work schedules. A woman might be grouped with different peers in group-education sessions and met with different educators during the trial. In this way, we could reduce the potential influence from educators and group peers.