Because arithmetical difficulties are not always recognized during elementary school, the field needs diagnostic tools for (young) adults. The number of instruments available for this population is nevertheless scarce and for the existing instruments standards for (young) adults are often lacking. Moreover, time pressure is a crucial factor in the diagnostics of dyscalculia in that age group. To give directions to the support of young adults with dyscalculia, teachers and therapists also need to have a clear picture of the weak and strong arithmetical abilities. To that aim, an overall picture of the different arithmetical abilities is necessary.
We present the Arithmetical Skills Profile, a diagnostic tool that consists of two major parts. The first part offers a profound investigation of the basic arithmetical abilities (arithmetical fact knowledge, procedural knowledge and performance, conceptual knowledge and the integration of these topics). The second part aims at detailed and individualized recommendations by analyzing daily life skills related to arithmetic, and possible ways of compensation.
In a pilot study we already observed a significant difference (F(1, 110) = 6.18, p<.05) between the scores of participants without and with dyscalculia (or a history of interventions for arithmetical difficulties), although in a restricted sample (n=140, of whom 15 experienced arithmetical problems).
In the present study we present the results of a large sample of 6th graders (secondary education), the reference group. Findings about the validity (using criteria such as having a dyscalculia diagnosis or not) and (test-retest) reliability of the instrument will also be presented.