The Multi-Tiered System of Support (MTSS) approach
The education model that currently prevails in many European countries for managing interindividual differences at school is the so-called « wait-to-fail » model (Brown-Chidsey, 2007), referring to the unfortunate trend to wait until a pupil is in serious academic difficulty before providing more appropriate pedagogical support. It has however been thoroughly demonstrated that once such gaps are established, they widen and are difficult and costly to reduce (Schweinhart, 2013). Based on these observations and since almost two decades now, the North American education systems are widely disseminating a specific school model aiming to prevent difficulties in the learning and behavioural areas by training teachers to intervene early (Fuchs & Fuchs, 2006; Jimerson et al., 2016).
Grouped under the umbrella term of Multi-Tiered Systems of Support (MTSS), the educational frameworks that are Response to Intervention (RTI, Fuchs & Fuchs, 2006) and Schoolwide positive behaviour interventions and supports (SWPBIS, Sugai & Horner, 2006) aim to increase equity and inclusion by improving the education academic and social emotional behavior outcomes of all students, especially those of the most vulnerable ones. Concretely, the MTSS model is typically conceptualized as a data-driven three-step approach piloted by a school team.
The primary prevention (Tier 1) is the evidence-based core instruction programme conducted by teachers, with periodical screenings made by the teacher or another member of the MTSS team to identify students at risk of poor learning outcomes or social-emotional behaviour (SEB). In theory, approximately 75-80 % of the students adequately respond to this high-quality and evidence-based Tier 1 instruction (Batsche et al., 2005). This first level is often considered the cornerstone of the model and the first place to prevent learning difficulties. The goal of Tier 1 is to ensure the success of most students by providing them with high quality or evidence-based teaching (Desrochers et al., 2016).
For the 20-25% students considered as at risk, more intense intervention (three to five 30 min sessions per week for 8-16 weeks) is then provided in small group (4-6 students) presenting the same kind of difficulties (Tier 2). These additional interventions can easily be implemented by regular teachers with specific training, resource teachers or educational trainees, especially when intervention programmes are well defined. MTSS specialists argue that approximately 5 % of students do not adequately respond to the Tier 2 evidence-based intervention, and that those would be the students eligible for learning and/or behaviour disabilities.
In Tier 3, intervention is even more individualised and intensive, extending over 16 weeks with four to five 45-60 min sessions per week (Austin et al. 2017, Vaughn, & McClelland, 2017). These interventions are usually delivered by specialized interventionists (special education teachers/orthopedagogy specialists, speech therapists, psychologists...) due to the degree of severity of the difficulties encountered and the complexity of the intervention programmes designed for them (Desrochers, 2021).
Therefore, one of the aims of the MTSS approach is to better distinguish between students with real learning difficulties who need special - and expensive - measures and those who have simply not received sufficiently effective first instance teaching. A fundamental feature of this model is thus the identification of at-risk students based on objective data. The use of such data minimizes the place of subjective judgments often made, even unconsciously, by teachers about children’s abilities (Paré & Prud’Homme, 2014). Another key feature of the model is the use of evidence-based education. This refers to education practices that have been found to be effective through rigorous research designs and aims at moving beyond personal impressions or beliefs about the practices that should be favoured (Slavin, 2002).