Scientific Research in Education was an attempt to articulate what is meant by quality with respect to scientific research in education. That book offered six principles that underlie all fields of scientific endeavor, including scientific research in education (National Research Council, 2002, p. 52):

1. Pose significant questions that can be investigated empirically.

2. Link research to relevant theory.

3. Use methods that permit direct investigation of the question.

4. Provide a coherent and explicit chain of reasoning.

5. Replicate and generalize across studies.

6. Disclose research to encourage professional scrutiny and critique.

In the scientific study of education, several features of teaching, learning, and schooling shape the ways in which the guiding principles are instantiated (e.g., the mobility of the student population). Together, the principles and the features provide a framework for thinking about the quality of scientific education research. We adopt this framework as our working definition of quality.

Recently, much attention has been focused on the methods used in education studies (most closely related to the third principle above), with a particular emphasis on randomized field trials to help establish cause-and-effect relationships (see, e.g., U.S. Department of Education, 2002, 2004; What Works Clearinghouse, 2004). Methods are the tools that researchers use to conduct their work; their appropriate use is essential to promoting quality.

Scientific Research in Education makes a number of important arguments related to methods. Specifically, the choice of method or methods must be driven by the question posed for investigation: no method can be judged as good, bad, scientific, or otherwise without reference to the question it is being used to address. In addition, scientific inferences are strengthened if they hold up under scrutiny through testing using multiple methods. A related and final point made in the book is that both quantitative and qualitative methods are needed to fully explore the range of questions about educational phenomena that are ripe for scientific study. The tendency in the current debates—in research, policy, and practice communities—to align with either quantitative or qualitative approaches is there-