Study on the Effect of Singapore Mathematics on Student Proficiency in a Massachusetts School District

This information is published in many places, but the information below comes from a blog entitled,
"Parents for a Quality Math Education" (PQME).
"In October 2009 Gabriella and Paul Rosenbaum Foundation released a report entitled The Effect of Singapore Mathematics on Student Proficiency in a Massachusetts School District:  a Longitudinal Statistical Examination. It shows that the longer students had Singapore Mathematics as their curriculum the better they performed on Massachusetts’s tests."