More worryingly, in the countries that distributed the PISA parent questionnaire, disadvantaged parents are significantly more likely than advantaged parents to report that "low expenses" and "financial aid" are very important factors to consider when choosing a school. While parents from all backgrounds cite academic achievement as an important consideration when choosing a school for their children, advantaged parents are, on average, nine percentage points more likely than disadvantaged parents to cite this criterion as "very important". These differences suggest that disadvantaged parents may believe that their choice of schools for their child is limited, due to the cost of some schools.