Science of reading

Reading models

Since the purpose of reading is to understand what we read, it is necessary to teach reading comprehension skills. However, it is important to recognize that decoding is a precursor skill to understanding.

Decoding/word recognition is the ability to accurately and quickly read the words on a page and it plays a critical role in reading comprehension.

When a child struggles with decoding, fluency is decreased, accuracy is compromised, errors occur, and the energy needed for comprehension is depleted by the effort required to simply decode.

The Simple View of Reading

Gough & Tunmer (1986) proposed the widely accepted view that reading comprehension (R) has two basic components: word-level decoding ability (i.e. word recognition) (D) and listening/oral language comprehension ability (C) (i.e. how well one understands spoken language) (Figure 1). It is called the ‘Simple View of Reading’ (Farrell et al 2010, Wren 2001).  Good readers have strong abilities in both components of reading.  If decoding or language comprehension is poor, then reading comprehension will be affected.

Figure 1 The Simple View of Reading

Gough & Tunmer (1986)

Simple View of Readingc2

The Simple View of Reading has been tested in over 100 studies (see Kilpatrick 2015 p. 47 for further discussion) and endorsed by many reading experts (eg. Linda Farrell & colleagues at the Center for Development & Learning (2010)).

Other investigators have further developed the Simple View of Reading by elaborating on the cognitive foundations of decoding (D) and listening comprehension (C). Wren (2001) elaborates that decoding ability (D) is a function of knowledge of print concepts, letter knowledge, phoneme awareness and knowledge of the alphabetic principle (linking letters with sounds) (Wren, 2001). Scarborough also includes sight recognition of familiar words (eg. fluency) (Scarborough, 2001). Listening/language comprehension (C) is a function of background knowledge, phonology, syntax, and semantics (Wren, 2001); Scarborough (2001) also includes vocabulary, verbal reasoning, and literacy knowledge.

Scarborough "Rope" model

These components of decoding (D) and oral language comprehension (C) (and ultimately skilled reading) are clearly identified in the “Reading Rope” model by H Scarborough (2001) (Figure 2). This graphic shows that skilled reading also depends on the integration of the decoding/word recognition skills for the development of automaticity (fluency), which is the hallmark of a skilled reader.

Figure 2   The Scarborough 'Rope' Model of Skilled Reading

Scarborough rope model

Scarborough, H.S. 2001. Connecting early language and literacy to later reading (dis)abilities. Evidence, theory, and practice. In S. Neuman & D. Dickinson (Eds.), Handbook for research in early literacy (pp. 97–110). New York, NY: Guilford Press.

Dyslexia and the reading models

Gough & Tunmer, among others, have identified ‘dyslexia’ as a disability in word recognition ability. Intervention for this reading difficulty must be targeted on the foundational skills required for good word recognition, including phonological awareness, phonics (ie. alphabetic principle, letter-sounds) and rapid recognition/decoding of familiar words.

Research has clearly identified poor phonological awareness as a risk factor for dyslexia.  Intensive phonological awareness instruction can be very helpful for many readers with dyslexia.

Many readers also struggle with the development of automaticity in reading (fluency).  This difficulty has been linked to poor ability in Rapid Automatized Naming, which is the ability to quickly name familiar objects on a page, such as objects or numbers but most significantly, letters.  Fluency instruction, such as repeated readings, speed drills can be helpful in improving fluency, however, this challenge is often more difficult to remediate than reading accuracy.

Difficulties in oral comprehension but not word recognition ability is much less common; this has been termed ‘reading-comprehension impairment’ (Hulme & Snowling, 2011) and is considered a distinct issue from dyslexia, although it is possible that some people have challenges with both dyslexia and reading comprehension impairment.

The reading model is helpful in understanding the foundational skills affected by dyslexia and that Structured Literacy instruction, which explicitly teaches these foundational skills, will help students with dyslexia become more accurate and fluent readers.

Farrell, L., et al. 2010. The Simple View of Reading. The Center for Development and Learning Blog. February 1, 2010. Retrieved from:

Hulme, C. & M.J. Snowling. 2011. Children’s reading comprehension difficulties: nature, causes, and treatments. Current Directions in Psychological Science. 20(3):139-142.

Kilpatrick, D. A. 2015. Essentials of Assessing, Preventing, and Overcoming Reading Difficulties. Wiley & Sons Inc.

Scarborough, H.S. 2001. A discussion of evidence, theory, and practice connecting early language and literacy to later reading disabilities. In Newman, S.B. & D.K. Dickinson (Eds.), Handbook of early literacy research. P. 98. Guilford Press, New York, NY.

Wren, S. 2001. The Cognitive Foundations of Learning to Read: A Framework. Southwest Educational Development Laboratory. Austin, TX.