Text Complexity with Dr. Tim Shanahan

How do we measure text complexity and predict reading comprehension?

Understanding text complexity — including what factors make a text complex, how that complexity is determined or measured, and how text complexity relates to student learning — isn’t a simple task. But for reading teachers, understanding the nuances of text complexity can be a powerful tool for promoting strong student reading comprehension. In the white paper below, literacy expert Dr. Tim Shanahan breaks down the research on text complexity and reading comprehension. Here’s some of what you can expect to learn in the white paper:

What Makes Text Complex?

While readability measures primarily rely on word sophistication and text complexity, there are many factors that contribute to the complexity of a particular text. In the white paper, Dr. Shanahan provides an in-depth explanation of these factors, many of which are challenging to measure, including:

  • Complexity of the ideas presented in the text
  • The way ideas connect with each other throughout the entirety of the text, which is called “text coherence”
  • Text structure or organization
  • The amount of background information provided
  • Use of literary devices, such as irony or metaphors
  • Presence of data representation tools, like graphs or charts
  • The student themselves

A note on this last factor: according to Dr. Shanahan, students contribute to the imperfect measurement of readability formulas because students bring different characteristics to the text, including background knowledge, motivation, and so on.

Text Complexity and Learning

After Dr. Shanahan spends time explaining what text complexity is and how it’s measured, he explores how text complexity relates directly to student learning.

Generally, scholars believe that it’s important to match text complexity to a student’s ability to read in order to maximize the learning that results from reading. But the consensus on exactly how to achieve that has changed over the years.

Initially, the general consensus was that a text appropriate for a particular student would be not too easy, not too hard, but just challenging enough that the student could learn from it while still comprehending it. But Dr. Shanahan explains that while this might seem like a simple notion, it can be complex to put into practice. There have been too few experimental studies to determine the optimal level of text complexity for learning. From what research we can reference, it would seem that educators should perhaps be providing students with slightly more complex texts than was believed in the past.

But, Dr. Shanahan explains, educators should be wary of that conclusion without considering the various other factors of reading comprehension. This is especially true for beginning readers, who have to first navigate the decoding system. For all students, it’s important to consider the other influencers on comprehension besides text complexity, including scaffolding, support, explanation, rereading, and motivation — much of which is dependent on the teacher.

In order to truly use text complexity to empower students to grow as readers, Dr. Shanahan suggests that educators need to gain a deep understanding of what text complexity is, be able to recognize it in texts themselves, and understand the various nuances of reading comprehension as it relates to instruction.

Read the full white paper here, or below:

For more research, see the McGraw-Hill Education PreK-12 Research Portal:

Then, check out this literacy video series, featuring Tim Shanahan on authentic text: