A Holyrood committee will investigate whether children in care who are in the family home would be better off if they were looked after elsewhere.
Members of the Scottish Parliament's Education and Culture Committee are to examine the issue after an inquiry into the educational achievements of children in care.
Committee convener Stewart Maxwell said: "During the inquiry it became clear that there is a sensitive and difficult balance to be struck between supporting families at home and intervening to remove children from harmful situations.
"That is why we have agreed to hold a further, detailed inquiry into this area."
Figures from the Scottish Government showed on 4.7% of children cared for outside the family home gained five qualifications or more.
This compares to just 0.5% of youngsters in care who remain in the family home.
Mr Maxwell said the committee had been told this group of children faced "particular disadvantages" including being exposed to substance misuse, domestic violence and neglect.
A report by the committee said there was "no doubt that children looked after at home have poorer levels of attainment than other looked after children".