The Effects of Treatment Integrity on Vocabulary Learning in Students Who are Deaf or Hard of Hearing

Abstract

The purpose of this study was to investigate the effects of a supplemental vocabulary intervention on the content area vocabulary word and definition knowledge of DHH student in grades K-2, the integrity with which itinerant teachers implemented the supplemental vocabulary intervention, and the effects and benefits of coaching to support treatment integrity. Mixed methods were employed; a single subject multiple baseline across subjects and content design was used to investigate student word and definition knowledge, while quantitative and qualitative methodologies were used to examine the effects of coaching on teachers' treatment integrity. The supplemental vocabulary intervention included explicit and implicit strategies and was designed to fit the context of itinerant teacher services. Various levels of support were employed to coach teachers as they gained familiarity with the intervention and improved their treatment integrity during implementation. Student word and definition knowledge was examined in relation to teacher treatment integrity to determine if teacher implementation had an effect on student outcomes. Results showed a functional relationship between the supplemental vocabulary intervention and student word and definition knowledge. Teachers' treatment integrity was found to have a greater effect on student definition knowledge than word knowledge. Teachers responded positively to the coaching they received, and their implementation improved over the course of the study. Practical and research implications for using supplemental vocabulary instruction with DHH students, as well as the need to provide support to teachers to improve treatment integrity, are discussed.