The Developmental Similarity (Continuity) Construct: A Commentary

Abstract

The primary focus of the present article is to describe the contributions of the developmental similarity (continuity) hypothesis to understanding the acquisition of beginning and mature reading comprehension skills. Some principles are common across several reading similarity models such as, for example, Scarborough’s Reading Rope Model, Simple View of Reading, and Paul’s Qualitative Similarity Hypothesis. In general, it is argued that, with qualifications, the developmental similarity (continuity) hypothesis applies to all readers, including struggling readers and those with disabilities. Buttressed by the Science of Reading, these models assert that all individuals need to acquire the same fundamentals for learning to read, to subsequently read to learn. These models present critical implications for instruction, curriculum, and assessment. Also discussed are challenges to the models resulting in a nuanced consensus, mainly with respect to variations in language access, self-regulation, and sociocultural variables. In essence, the developmental similarity construct has contributed to a shift from explanations of reading acquisition, based predominantly on deficits or disabilities, to an emphasis on interventions that incorporate relevant instructional strategies, based on fundamentals. Recommendations for further exploration are presented in the concluding section.