Should science guide practice in special education? Most individuals would say "Yes." However, the "devil is in the details." Major initiatives in other disciplines such as medicine, the allied health professions, and psychology are attempting to identify and disseminate practices that have scientific evidence of effectiveness. In education, national policies such as the No Child Left Behind Act (NCLB) require that teachers use scientifically proven practices in their classrooms. Yet, there is concern about the quality of scientific research in the field of education and disagreement about the type of scientific information that is acceptable as evidence (White & Smith, 2002). An oft-cited report from the National Research Council (NRC) states that science in education consists of different types of questions and that different methodologies are needed to address these questions (Shavelson & Towne, 2002). In contrast, other agencies and research synthesis organizations (e.g., the What Works Clearinghouse [WWC]) have focused primarily on the question of whether a practice is effective and proposed that the "gold standard" for addressing this question is a single type of research methodology--randomized experimental group designs (also called randomized clinical trials or RCTs; WWC, 2003b).
In January 2003, the Council for Exceptional Children's (CEC) Division for Research established a task force to address these devilish details as they apply to special education. The operating assumptions of this task force were that different types of research questions are important for building and documenting the effectiveness of practices, and that different types of methodologies are essential in order to address these questions. The task force identified four types of research methodologies in special education: (a) experimental group, (b) correlational, (c) single subject, and (d) qualitative designs. The task force was to establish quality indicators for each methodology and to propose how evidence from each methodology could be used to identify and understand effective practices in special education. The subsequent four articles in this issue of Exceptional Children will describe the quality indicators and provide guidelines for how each methodology contributes evidence for the effectiveness of practices in special education.
This article provides a context and rationale for this endeavor. We begin with a discussion of the importance of multiple scientific methodologies in special education research. Next, we examine efforts to identify high-quality research methodology and then examine initiatives in the fields of medicine and education to identify evidence-based practice. In conclusion, we propose that research and development on effective practices in special education exists on a continuum, with each methodology matched to questions arising from different points of the continuum. Also, it is important to acknowledge that although basic research serves as the foundation for the development of effective practices and is critically important for our work in special education, the issues addressed in this article will be most relevant for applied research.
RATIONALE FOR MULTIPLE SCIENTIFIC RESEARCH METHODOLOGIES IN SPECIAL EDUCATION
The rationale for having different research methodologies in special education is based on the current conceptualization of research in education and the complexity of special education as a field. The history and tradition of special education research, when employing multiple methodologies, has resulted in the identification of effective practices.
CURRENT CONCEPTUALIZATION OF RESEARCH IN EDUCATION
A primary emphasis in education policy today is to improve the quality of education for all of America's children. This policy, exemplified by NCLB, compels educators to use "teaching practices that have been proven to work" (U.S. …