The specification of it being "mothers" not "parents" or "primary care-givers" - assuming scientific rigour - must be important.
I am disinclined to assume such scientific rigor as the explanation for that wording. I am much more inclined to assume unquestioned bias on the part of the people who wrote and administered the study. We have peer reviewed journals et al to help account for the fact that humans are pretty darn bad about being human, no matter their job title. But, ultimately, it is essentially impossible to weed out bias entirely.
I hope you are right and I am not but I see no reason at this time to think so.
I am disinclined to assume such scientific rigor as the explanation for that wording. I am much more inclined to assume unquestioned bias on the part of the people who wrote and administered the study. We have peer reviewed journals et al to help account for the fact that humans are pretty darn bad about being human, no matter their job title. But, ultimately, it is essentially impossible to weed out bias entirely.
I hope you are right and I am not but I see no reason at this time to think so.