There has been a lot of research into dyslexia for more than 100 years. Some of it is excellent, and some of it is dubious. To be sure, it is complicated and it is widely misunderstood. Hopefully, from working in the field as both researchers and practitioners for more than 20 years, we understand the challenges of the reseachers and, more importantly, the dyslexic individual themselves.
That research has involved the cognitive assessments and the self-assessment questions that are used in this screening tool. Based on research from more than 18,000 individuals, and using a continuous integration process (i.e. we are never happy unless we can make evidence-based improvements), the tool has reliability measures (alpha) in the category of Excellent, and has been repeatedly recommended in diverse context as the tool of choice by professional and end users looking for a well-developed tool that will guide further work, including a possible full (human) assessment.
Below are a few papers that may be of interest to you. They are chosen to show the types of questions we like to ask, and the challenges that we raise within a research environment, all of which help inform the development of our evidence-based Profilers.
Smythe I (2015) Composite scores: Do categories and dimensions offer real support? British Psychological Society.
Smythe I (2015) What makes a good concept definition for disabilities? A case study of executive function. British Psychological Society.
Smythe I (2014) The difficulties of finding appropriate norms for assessing adults for dyslexia. Assessment and Measurement. British Psychological Society.
Smythe I (2014) Inconsistencies in Dyslexia Assessment. Assessment and Measurement. British Psychological Society.