TABLE 2.

Elements of dyslexia definitions, and their implications for research and remedial education, in the past and future.

Conceptual element of definition		Implications for research		Implications for remedial education
Past	Future	Past	Future	Past	Future
Discrepancy from IQ	Across ability range	Ignore children below average IQ	Include at least low average IQ	Exclude low-IQ cases	Include all poor readers
Diverse symptom list	Word-level processing	Seek common causes	Focus on reading skill	Highlight and left suboptimal functions	Concentrate on reading-related profile
Single word decoding	Word reading difficulty	Measure accuracy	Accuracy and fluency	Set decoding targets	Also work on fluency
Discrete identifiable condition	Continuous with the general population	Define and debate diagnostic criteria	Characterize performance profiles	Clear cut-off criteria	Multi-factorial choices
Caused by X (factor accounting for all)	Multifactorial, multi-level, polygenic	Search for distinct cause(s)	Seek developmental pathways	Try to fix X (expect reading to improve)	Focus on reading, build on strengths
Determined by genes; fixed at birth	Interplay of multiple interacting factors	Seek cures or look for support potential	Study environmental changers	Try to cure or to circumvent; any time	Change early conditions to improve outcomes
Neurodevelopmental disorder	Within normal variability	Look for abnormality	Study variability	Label as disordered, afflicted, impaired	Identify weak areas; provide support
Natural category	Educational label	Ask what dyslexia is	Ask how to help	Treat as different kind	Contextualize and guide