When evaluating schools and education reform initiatives, analysts (and the policymakers who depend on them) are often hampered by poor data. Conclusions about school and program effectiveness would be far more robust if states had a mechanism for linking student test scores over time. In testimony prepared for the California legislature, which is considering a bill that would create such a data system for the state, RAND???s Laura Hamilton outlines some advantages of using unique student identifier numbers to link student records over time: this would allow researchers to remove the effects of student mobility from their analyses, to examine pupils??? transitions from one school to another, and to answer questions about the growth trajectories of different types of students. ???A statewide I.D. system would dramatically improve the quality of research and evaluation that can be done on local and state initiatives,??? Hamilton concludes. It was in part because of the inadequacies of the state???s current data system that researchers have been unable to agree on the impact of the state???s massive effort to reduce class size. The No Child Left Behind Act, which requires annual testing in grades 3-8, will create a treasure trove of data for researchers in states that are game to link student records over time using unique identifiers. The privacy issues can readily be dealt with. Whether the political issues - the many forces that don???t want robust evidence on schools??? and educators??? effectiveness over time - can be laid to rest is quite another matter. ???Benefits of a Statewide Student Identifier System for California,??? by Laura Hamilton, Testimony Presented to the California State Senate Education Committee, April 24, 2002
