Fidelity of implementation in a randomized controlled trial study: The effect of virtual professional development on bilingual teachers

Using a low-inference observation instrument, we investigated the effect of an ongoing, intensive, and structured virtual professional development (VPD) based on the fidelity of implementation (FOI) across treatment and control conditions in a randomized controlled trial validation study implemented in 116-bilingual classrooms in seven Texas school districts. Virtual observations were collected three times at the beginning, middle, and end of the school year. Both quantitative and qualitative results indicated that VPD significantly impacted bilingual teachers' fidelity of implementation. Treatment teachers outperformed teachers in control condition in the areas of student involvement, leveled questioning, applying ESL strategies, providing affective and cognitive feedback, and presenting more English material to encourage English learners to participate in classroom activities.