Dorien Bangma

268 | SUMMARY ADHD test battery. In comparison to a healthy control group (n = 51; age range 20 – 64 year; 51.0% male), adults with ADHD showed significantly lower performances on the two tests of financial competence (measuring financial knowledge and financial judgment). A mediation effect of numeracy was found for this relation (indirect effect), however, group differences on these tests remained statistically significant after controlling for numeracy (direct effect). Adults with ADHD had also more difficulties with decision making with implications for the future, showed a stronger tendency to buy on impulse and made more often use of two inadequate financial decision styles (i.e., the avoidant and spontaneous decision style) compared to healthy controls. Numeracy and other cognitive domains assessed (e.g., processing speed, working memory or inhibition) could not explain the group differences that were found for these aspects of FDM. Compared to the mean scores and standard deviations of the healthy control sample, one out of three adults with ADHD (i.e., 34.2%) showed a normal performance on all measures of FDM. However, 26.7% adults with ADHD showed a very low/impaired performance and an additional 28.9% showed a low performance on one or more FDM tests. This is twice as often as in healthy controls (i.e., 19.6% and 7.8% of the healthy controls showed a very low/impaired or low performance, respectively, on one or more FDM tests). Furthermore, adults with ADHD reported to have a significantly poorer financial situation than healthy controls, including having less income, more often debts and less often using a savings account. Patients were off-medication 48 hours prior to participation; therefore, it is unclear if there were any effects of the use of stimulant medication on the FDM performances of patients. Furthermore, the onset of medication use and other ADHD treatments were not taken into account. Both can have an influence on the abilities of individuals with ADHD to develop adequate FDM capability skills. Nevertheless, taking several limitations into account, it can be concluded that adults with ADHD have difficulties with several aspects of FDM. These difficulties may at least partly explain the poorer financial situation of adults with ADHD. The study presented in chapter 8 further evaluates the effect of symptoms of ADHD on two aspects of FDM (i.e., the tendency to buy on impulse and the use of financial decision styles). Additionally, the influence of personality, symptoms of depression and demographics on the association between symptoms of ADHD and these aspects of FDM is evaluated. For this, a community sample of 1292 participants (age range 18–93 years) completed online questionnaires evaluating symptoms of ADHD, impulsive buying, financial decision styles, personal financial situation, symptoms of depression and personality traits. Consistent with previous results ( chapter 7 ), individuals meeting the clinical criteria of adult ADHD based on a self-report ADHD questionnaire (i.e., ADHD group, n = 45) reported a stronger tendency to buy on impulse and more often used an avoidant or spontaneous financial decision style compared to individuals without symptoms of ADHD (i.e., No ADHD group, n = 265). However, using hierarchical multiple regression analyses, current symptoms of ADHD were found not to be related to impulsive buying and financial decision styles. Instead, traits of neuroticism and/or extraversion were positively related to these aspects of FDM. Traits of conscientiousness and agreeableness were also found to be related to the use of some decision styles (i.e., rational, avoidant and spontaneous decision style) and with more impulsive buying