Field Studies of RTI Effectiveness Tiers of Reading Intervention (TRI)

Study Citation


O’Connor, R. E., Harty, K. R., & Fulmer, D. (2005). Tiers of intervention in kindergarten through third grade. Journal of Learning Disabilities, 38, 532–538..

Program Description

The tiers of reading intervention (TRI) is a problem-solving model that includes collaborative consultation. It is a tiered model wherein students not achieving desired results in response to universal, evidence-based instruction receive increasingly intensive interventions before being referred for special education evaluation. O'Connor, Harty, and Fulmer (2005) identified three tiers of the TRI process: a) professional development and evidence-based instruction, b) small-group instruction three days per week, and c) daily small-group or individual instruction.

Within this model, general education teachers are responsible for implementing the evidence-based instruction (e.g., reading instruction based on the findings of the National Reading Panel). Nonresponders to evidence-based instruction (e.g., behind peers on phoneme awareness and letter knowledge and poor progress in response to general class instruction two months after the initial screening) move to Tier 2 intervention. Twenty-two students received Tier 2 and/or Tier 3 instruction.

Theoretically, a team of general education teachers, special education teachers, and other school personnel would develop a plan for individual interventions at Tier 2 and Tier 3. In this study, however, university researchers carried out Tier 2 and Tier 3 intervention development and implementation. Additionally, training of school personnel for Tier 1 evidence-based instruction was the responsibility of university researchers and was carried out over multiple sessions across the school year.

Purpose of Study


O'Connor et al. (2005) conducted the study to identify effects of the TRI model on student reading outcomes and special education placements. Specifically, the purpose of the study was to answer the following questions:


  1. What is the effect of Tier 2 and Tier 3 interventions on word identification, word attack, passage comprehension, and fluency compared to a control group over a four-year period?
  2. What is the effect of Tier 2 and Tier 3 interventions on special education placements compared to a historical control group (same schools and teachers) after four years of implementation?

Study Method


K–3 students (100 students per grade level) from two schools participated in the study. Teachers were provided intensive professional development in evidence-based instruction for the first three months of the study to improve instruction and decrease the possibility that students were selected for Tier 2 intervention due to poor instruction. Students deemed nonresponsive to Tier 1 instruction received small-group instruction in the general education classroom for 20–25 minutes three times per week. Students nonresponsive to Tier 2 intervention received one-to-one or two-to-one instruction for 30 minutes, five days per week. University researchers implemented Tier 1 and Tier 2 interventions.


Study Results

Question 1: O'Connor et al. (2005) reported that students receiving Tier 2 and Tier 3 interventions showed improvement on all reading measures when compared to a historical contrast group from the same school.

Question 2: For the historical contrast group, the incidence of placement in special education averaged 15%. Following 4 years of participation in this study, the rate of placement was 8%.

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