The importance of assistive technology for individuals with visual impairments to live good-quality lives can never be overemphasized. In recognition of its essential benefit, the Individuals with Disabilities Education Improvement Act (2004) continues to demand that students' Individualized Education Programs include a consideration of assistive technology. However, evidence has shown that assistive technology is underutilized with students with visual impairments. For example, in a survey of the use of assistive technology among primary and secondary students with visual impairments in Illinois, Kapperman, Sticken, and Heinze (2002) found that 33.3% of students with visual impairments in nonitinerant placements and 73% of those in itinerant placements did not use assistive technology. They noted that "60% of the students who, in the authors' judgment, could benefit from the use of assistive technology were not given the opportunity to use it" (p. 107). Kelly (2009) found that nationwide, 59% to 71% of the primary and secondary students with visual impairments who were most inclined to benefit from assistive technology did not have the opportunity to use it from 2000 to 2004.
What are the barriers that hinder the use of assistive technology by students who are visually impaired? Although there are many, mounting evidence shows that a major reason is that teachers of students with visual impairments lack adequate knowledge to provide effective instruction in assistive technology (Abner & Lahm, 2002; Edwards & Lewis, 1998; Kapperman et al., 2002; Lee & Vega, 2005; Parker et al., 1990; Zhou, Parker, Smith, & Griffin-Shirley, 2011). A contributing factor to teachers' gap in knowledge may be the lack of training in assistive technology in current teacher training programs. For example, many teacher training programs for special educators do not yet include courses or even class sections on assistive technology (Lahm, 2003; Lee & Vega, 2005; Wahl, 2004) or do not require assistive technology courses for certifying teachers (Judge & Simms, 2009). In many graduate-level programs, there is a significant discrepancy in the integration of assistive technology on the basis of the program coordinators' perceptions (Michaels & Mcdermott, 2003).
Recognizing that one possible reason for inadequate preservice preparation in assistive technology for teachers of students with visual impairments was that a separate set of assistive technology competencies did not exist to guide programs on which assistive technology content to teach, Smith, Kelley, Maushak, Griffin-Shirley, and Lan (2009) conducted a Delphi study to develop a set of assistive technology competencies that teachers of students with visual impairments should possess upon completion of their teacher training programs. A panel of 34 experts in the field of visual impairment, representing all major geographic regions in the United States with various professional viewpoints, participated in the study. Building on a high level of consensus among these experts, Smith et al. developed a set of 111 assistive technology competencies and determined the expected levels of expertise upon completion of a program. These 111 competencies were divided into 10 domains: (1) foundations of assistive technology, (2) disability-related assistive technology, (3) use of assistive technology, (4) assistive technology instructional strategies, (5) learning environments, (6) access to information, (7) instructional planning, (8) assessment, (9) professional development, and (10) collaboration.
Recognizing certain limitations of the Delphi technique, Smith et al. (2009) recommended that future studies be conducted to validate their findings, including a large-scale survey of teachers of students with visual impairments. Agreeing to the importance of and need for a valid set of competencies in assistive technology for the preparation of high-quality teachers of students with visual impairments, we conducted the study presented here to compare previous experts' opinions with the opinions of practicing teachers of students with visual impairments regarding what levels of expertise in assistive technology that teachers of students with visual impairments should possess. …