The Simple View of Reading: R=DxC

Many models have been put forth to describe the essential elements involved in reading, but none has proven to be as robust and useful as what Philip Gough described as the “Simple View” of reading. In this model, there are two general elements that are equally important to reading comprehension — they are decoding skills and language comprehension skills.
Put differently, a person’s ability to read and understand text can be predicted if you know that person’s ability to decode words and that person’s ability to understand spoken language. If a child is rapid and fluent at decoding text (unfamiliar words or pseudowords for preference), AND that child has no difficulty understanding spoken language (implicit understanding of more formal language for preference), then you can safely predict that child will not have difficulty with independent reading comprehension.

Research has shown repeatedly that, in broad strokes, when there are deficits in reading comprehension, there are always deficits in either language comprehension or decoding skills, or both — in fact, most typically both. There are some children (although it is rare) whose reading comprehension suffers because, while they are very good at understanding spoken language, they are poor at decoding text — these children are called true dyslexics. There are other children (although very rare) whose reading comprehension suffers because, while they are good at decoding text, they have difficulties understanding spoken language — these children are called hyperlexics. Most commonly, when a child has difficulty with reading comprehension, they are having difficulty with both decoding and language comprehension — these children are described as having garden variety reading difficulties.

It also makes sense to think of the relationship between these three variables mathematically, where reading comprehension is the product of decoding and language comprehension, or as Gough put it, R=DxC where

R = Reading comprehension
D = Decoding skills and
C = Language comprehension

Imagine that each of these variables can range in value from 0 to 1. Somebody with perfect ability in one area would get a 1, and somebody who completely lacks ability in that area gets a 0 (with most people falling somewhere in between). It makes sense to think of the relationship as multiplicative, then, because if you a child is lacking in either decoding skills (D) or language comprehension skills (C), then reading skills (R) comparably suffer.

Consider a child who gets a perfect score on a language comprehension assessment (a score of 1), but who performs poorly on a decoding assessment (a score of 0). This model would predict that child would perform poorly (a score of 0) on a reading comprehension assessment.

If D=0 and C=1, then DxC = 0

And in fact, that is what is found when real children are tested. Children who are poor at decoding isolated words are also poor at reading and understanding text, regardless of how good they are at understanding language. Similarly, children who are poor at understanding language are poor at reading and understanding text, regardless of how good they are at decoding words. Researchers like Ron Carver have confirmed these predictions many times over.

And the other side of the coin has also been confirmed — children who are good at decoding isolated words (fast, fluent, and accurate) and who are good at understanding spoken language are, on the whole, quite good at reading and understanding connected text. The predictions made by the Simple View of Reading have been confirmed many times over.

Given that the formula R=DxC accurately describes reading, the implications become immediately obvious. First, we as educators must learn what it takes to help children to be both good decoders and good language comprehenders. And second, we should structure our assessment around this model.

There is a framework of reading acquisition based on the Simple View that addresses the first implication — this framework outlines the essential cognitive elements that research has shown to be important in the development of good decoding skills and good language comprehension skills. The complete PDF version of the framework document can be download here for free, or an on-line interactive version of the framework is available at the Southwest Educational Development Laboratory website.

Structuring assessment information around this framework is trivially easy — there is an on-line reading assessment database that allows you to search for published assessments that test specific knowledge domains that are outlined in the framework. Further, there is an overview document describing how each of these assessments is typically assessed. There are several ways to test a child’s knowledge of, for example, phoneme awareness, and this document describes the different assessment approaches that can be used to get information about a child’s growth in each of these knowledge domains.

Beginning of the year Simple Informal Student Reading Survey (for grades 2-8)

By September of every school year, teachers should be able to answer this question — how well do each of your students read?

More specifically, how many students in your class this year are having difficulties with reading? Do their difficulties stem from problems with decoding fluency or language comprehension? Or both?

This is the first question that I try to answer when I encounter a student struggling with reading — is it a decoding problem or a language comprehension problem? The Simple View of reading (R=DxC) tells us that difficulties with reading comprehension (R) stem from problems with decoding (D) or comprehension (C). Or both. Determining this is the first step in diagnosis, and it is the first step in planning intervention and effective instruction.

Language comprehension problems are easy enough to identify — if a student has trouble reading a passage of text, just read the passage of text out loud to the student. If the student can understand the passage when she listens to you read it aloud, then her language comprehension skills are not preventing her from understanding the text. She understands the material — she just can’t read it independently. It must be a decoding problem.

Decoding is a little thornier, but not much. Most students with decoding problems are able to correctly identify words and “attack” unfamiliar words — they just do it very, very slowly. Those students have problems with decoding fluency. That’s good news because fluency instruction is quite easy. Some students, however, are not able to accurately identify words — especially unfamiliar words they have not seen before. Those students have more basic word identification issues. These issues may stem from a lack of phoneme awareness or problems understanding the alphabetic principle.

To help teachers (2nd to 8th grade) to determine the reading instruction needs of each of their students, I’ve created a Simple Formative Reading Survey (available in PDF). Following this quick survey will help teachers to figure out what reading-related areas need more instructional support.