Voucher Study Indicates No Steady Gains in Learning
The study by the Rand Corporation, released here Thursday, was neither a death knell for the school- choice movement nor a ringing endorsement. Rather, it revealed the paucity of reliable data from either side. For example, though the report reviewed hundreds of studies, the authors found only three on the crucial question of student achievement whose methodology they considered sound.
http://www.nytimes.com/2001/12/09/education/09RAND.html?todaysheadlines&pagewanted=all