
When it comes to reading intervention, few programs are as widely known, or as hotly debated, as the Orton-Gillingham (OG) approach. Marketed as a lifeline for children with dyslexia and word-level reading disabilities (WLRD), OG is often touted as the gold standard. But is it? A closer look at the evidence tells a far more complicated story.
What Is Orton-Gillingham?
OG is described as a “direct, explicit, multisensory, structured, sequential, diagnostic, and prescriptive way to teach reading and spelling” (OG Academy, 2020) and is frequently recommended for students with reading difficulties, including dyslexia. In theory, that checks a lot of boxes for evidence-based instruction. And indeed, certain components of OG are backed by strong research, specifically its explicit systematic and sequential instruction, diagnostic and responsive teaching, as well as scaffolding and guided practice (Austin et al, 2023).
What the Research Says (and Doesn’t Say)
A 2021 meta-analysis by Stevens and colleagues analyzed 109 articles and 24 studies of OG and OG-based interventions. The findings were underwhelming: OG interventions did not lead to statistically significant improvements in word reading, phonics, fluency, vocabulary, or comprehension. While there was a positive effect size (ES = 0.32 for foundational skills and 0.14 for vocabulary and comprehension), the results were not robust enough to confidently claim that OG is more effective than other forms of structured phonics instruction (Stevens et al., 2021).
This aligns with earlier reviews, such as Ritchey and Goeke (2006), which found limited research and weak evidence supporting OG instruction. Similarly, the What Works Clearinghouse evaluated a range of OG-based programs, both branded (commercially published) and unbranded (based on OG principles but not commercially packaged), and consistently found little evidence to support their effectiveness WWC, 2010a; WWC, 2010b; WWC, 2010c; WWC, 2010d; WWC, 2010e; WWC, 2010f; WWC, 2010g; WWC, 2010h; WWC, 2010i; WWC, 2012; WWC, 2013).
The Multisensory Myth
Much of Orton-Gillingham’s appeal and marketing rely heavily on its multisensory features like tracing letters in sand, air-writing, and tapping out sounds. But there’s a problem: the research base doesn’t support these components as essential or uniquely effective (Nicholson, 2011). Moats and Farrell (1999) noted that the kinesthetic aspects of OG have little empirical grounding. More recently, Schlesinger and Gray (2017) directly compared a structured literacy approach to a multisensory version and found no added benefit of multisensory methods on letter naming, sound production, word reading, or spelling. Both approaches yielded gains, but the multisensory elements did not confer any measurable advantage, even for students with dyslexia. Despite its popularity, the multisensory component lacks research support and should NOT be treated as an essential or evidence-based element of instruction.
OG Is Not One Program
One challenge in evaluating OG is that there’s no single “OG program.” It’s an umbrella term encompassing approximately 17 branded approaches (e.g., Alphabetic Phonics, Barton Reading and Spelling System, Fundations, Herman Method, Wilson Reading System, Project Read, Dyslexia Training Program, Project ASSIST, Slingerland Approach, Spalding Method, Starting Over, Language!, Lindamood Bell, Recipe for Reading, S.P.I.R.E., Take Flight, Writing Road to Reading, etc.), all with slightly different implementation models (Stevens et al, 2021; Nicholson, 2011). That variability makes it difficult to study with any consistency or draw broad conclusions about its effectiveness.
Same Label, Completely Different Methods
Because OG isn’t a single program, implementation varies widely between individual clinicians. Two practitioners using “OG” may be delivering entirely different interventions in content, pacing, and fidelity (Stevens et al, 2021). Some may stick closely to systematic phonics, while others lean heavily on unproven multisensory routines. That flexibility means clinicians can and often do, do whatever they want under the OG umbrella. But variability isn’t a strength when it undermines consistency and fidelity. When there’s no consistent evidence-based core, calling something “OG” is often more about the label than about what’s actually being taught.
The Bigger Problem: OG Doesn’t Address Oral Language Deficits
Even when OG improves decoding, it falls short for children with oral language deficits, and that’s a serious problem! OG is built around phonological awareness, decoding, and spelling. It doesn’t directly address core language skills like syntax, morphology, discourse organization, or inferencing. Some programs may touch on vocabulary or comprehension, but these elements are usually embedded within phonics tasks, not taught as part of a comprehensive language intervention. As Stevens et al. (2021) point out, OG interventions target word-level reading outcomes, not the underlying language comprehension deficits that drive reading struggles in many students, especially those with Developmental Language Disorder (DLD) or mixed profiles. And the research is clear: weaknesses in oral language, vocabulary, grammar, listening comprehension, and verbal reasoning are a major cause of reading difficulties, particularly in comprehension (Snowling & Hulme, 2025). For these students, decoding alone isn’t enough. They need explicit, structured language intervention.
Snowling and Hulme (2025) emphasize that oral language deficits, particularly in vocabulary and narrative development, are not just correlated with reading difficulties but are a core causal risk factor. Many children with dyslexia or poor reading comprehension also have underlying language impairments that often go unrecognized. Crucially, the authors argue that phonics instruction alone is not sufficient. To support long-term reading success, especially in students with Developmental Language Disorder (DLD) or mixed reading profiles, intervention must explicitly and directly target oral language skills. Early, comprehensive language-focused instruction is essential, not optional, for addressing the full range of difficulties that contribute to reading failure. Interventions that focus only on phonics can leave these students behind. OG programs, as typically delivered, do not adequately address the higher-order language skills required for reading comprehension, written expression, and overall academic success.
Why This Matters
The stakes are high. Orton-Gillingham (OG) isn’t just popular, it’s increasingly state-mandated. Several states have passed laws requiring or heavily promoting OG-based instruction for students with dyslexia. Arkansas mandates that all approved literacy programs align with the science of reading and include OG components (Arkansas Senate Bill 153, 2019). Mississippi defines dyslexia therapy and therapist training in OG terms and requires OG-trained coordinators in every district. Rhode Island goes even further, requiring OG-certified teachers, OG-based interventions, and OG-aligned preservice training, with state funding to support it (Rhode Island House Bills 5426 and 7968, 2019). Wisconsin mandates a state dyslexia specialist certified in OG and offers grants for teacher training (Wisconsin Assembly Bills 50 and 595; Senate Bill 555, 2019). Missouri, North Dakota, and Minnesota support OG through staff training requirements or funding (Missouri House Bill 2379; North Dakota House Bill 1461; Mississippi House Bill 1046; Senate Bill 2029; House Bill 496, 2019). These policies have elevated OG to a preferred or, in some cases, exclusive status, even though the research base is mixed. Teachers spend thousands on OG certification. Schools adopt it, assuming it’s “the science of reading approved.” But as Stevens et al. (2021) point out, OG’s widespread adoption has outpaced the strength of its supporting evidence.
And there’s a troubling opportunity cost: when OG is treated as the full solution, children who need language intervention don’t get it. They may “learn to decode” but still struggle to comprehend, think critically, or express themselves in writing.
So What Should We Be Doing?
There’s no need to discard OG if you’re already using it within a structured, explicit framework. But it’s not essential if your interventionist is already implementing an evidence-based, systematic, synthetic phonics approach; OG doesn’t offer anything uniquely necessary beyond that. And while it may support early decoding, on its own, it’s NOT sufficient to meet the full range of language and literacy needs most students with learning needs face.
To truly meet the needs of struggling readers, interventions must go beyond phonics and integrate:
- Explicit vocabulary instruction, including techniques like semantic feature analysis and context-based word learning, to build word knowledge essential for comprehension and expression (Beck, McKeown, & Kucan, 2013; Nagy & Scott, 2000; Nippold, 2018; Zipke, Ehri, & Cairns, 2009).
- Sentence structure, morphology, and grammar to support syntactic understanding in both oral and written language (Balthazar & Scott, 2018; Scott & Balthazar, 2010, 2013; Apel & Diehm, 2014).
- Discourse-level interventions such as explicit instruction in narrative and expository text structures, to strengthen comprehension, inferencing, and written composition across genres (Spencer & Petersen, 2020; Ukrainetz, 2024).
- Pragmatic language skills to help students interpret and participate in conversations, classroom discussions, and written exchanges appropriately and effectively (Lavi, 2020).
- Reading fluency with targeted practice to improve rate, accuracy, and prosody for clearer and more automatic reading (Samuels, 1997).
- Reading comprehension through strategies that build background knowledge, inferencing, and cohesive understanding of text (Wijekumar et al, 2023).
- Spelling using systematic instruction in phoneme-grapheme correspondences, syllable patterns, and morphology (Wasowicz et al., 2012).
- Written expression including planning, organizing, and revising ideas for clarity and coherence across sentence and paragraph levels (Laud & Patel, 2025).
OG’s emphasis on structured phonics is a helpful starting point, but without these additional components, it falls short for students with broader language-based learning needs.
These aren’t optional add-ons; they’re essential components of effective integrated intervention, especially for children with language-based learning disabilities, which is what dyslexia is.
Bottom Line
OG isn’t a magic bullet. It’s a collection of practices, some grounded in evidence, others not, that focus mostly on decoding. While it may benefit some children in the early stages of learning to read, current research doesn’t support it as a stand-alone solution. If we’re serious about helping poor readers, especially those with DLD or reading comprehension challenges, we need to stop treating OG as essential and start viewing it as optional. We could take it or leave it, because when children receive evidence-based synthetic phonics along with strong oral language intervention, OG offers nothing unique that can’t be achieved through better-supported methods. The real priority is comprehensive, contextualized language-focused instruction, not reliance on brand-name programs. This means integrating language and literacy goals across all aspects of intervention, connecting decoding with vocabulary instruction, linking syntax to comprehension, and embedding oral discourse within reading and writing tasks. Students make the most progress when instruction reflects the interdependence of language and literacy, not when they’re taught in isolation or delivered through rigid, trademarked programs, gimmicks, or disconnected from academics, routines. Effective service delivery requires a unified, research-based approach that addresses the full range of skills struggling readers need to thrive.
References:
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