While they might have caused some fear of masks in the 30 infants, they also should have tried faces with clown makeup to see if that also affected them. It could just have been a reaction to the non normal colors of faces that caused them to react.
@geniusmusing Yes. I still suspect that this will be non-replicable. But I can think of a few things they don't seem to cover,
* Did they give the parents any pychological tests to measure their fear reactions? * Did they take parents' stool samples? * Did they swab and culture the mothers' nipples for enterobacteria?