[humanistbot]

Their methodology/protocol paper for the study is open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2987778/

tl;dr: Students at schools in both the control and intervention groups took the standard required health class, which includes traditional sex ed. Students at schools in the intervention group had to opt in to the baby simulator. It wasn't a regular class and was independent of the required health class, but it did take place at the school. It was one week, 40 minutes a day to learn about the baby simulator and a few other basics. Students at schools in the intervention group only cared for the baby for 64 hours: 4 days x 16 hours. 'Free childcare' was mandated for the 8 hours they were at school, as they were turned off during the school day.

[webel0]

Thank you. I believe this answers my question:

> Individual participants were not blinded to their group assignment and upon giving consent were aware whether they were participating in the VIP intervention or control arm of the Trial.

So my read of the results is that participants who were interested in having a child (and were in an intervention school) selected into the VIP program. Participants in the control schools were a more random group.