They claim her research is faulty because it was based on subject interviews by an anthropologist rather than a survey by whomever.
If she had been interviewing young pregnant girls seeking an abortion, this would have been blazoned on the front page of the NYTimes and everyone would be screaming how bleeping brilliant an interviewer she is.
Interview is an acceptable research technique. What it lacks in breadth it makes up for in depth and clarity.
Instead of asking 2000 people the same 25 questions, you subject 25 people to extensive interviews over time.