Measuring Text Complexity: Three Factors
Qualitative evaluation of the text
Levels of meaning, structure, language conventionality and clarity, and knowledge demands
Quantitative evaluation of the text
Readability measures and other scores of text complexity
Matching reader to text and task
Reader variables (such as motivation, knowledge, and experiences) and task variables (such as purpose and the complexity generated by the task assigned and the questions posed)
More detailed information on text complexity and how it is measured is contained in Appendix A.