Dorien Bangma

GENERAL DISCUSSION AND CONCLUSION | 215 stabilization or even improvement of cognitive functioning over time (Manly et al., 2008; Visser et al., 2006), which in turn can have an influence on the FDM capability of these patients. Financial decision-making capability in adults with attention-deficit/hyperactivity disorder Besides the evaluation of patients with NDDs, several studies in this thesis (i.e., chapters 6, 7 and 8 ) focused on the (financial) decision-making capability of adults with ADHD. After systematically evaluating the literature ( chapter 6 ), evidence was found that adults with ADHD have more problems with decision-making compared to healthy individuals. This evidence is, however, relatively weak and results were found to be mixed. Inconsistent findings between studies might be related to interindividual differences between patients with ADHD, both within and between studies, such as comorbidities and medication use. For example, methylphenidate improved the decision-making capability of adults with ADHD according to two double blind placebo-controlled medication studies (Mowinckel et al., 2017; Sethi et al., 2018), although this positive effect of methylphenidate was not found on two other decision tasks (Agay et al., 2010, 2014). Further evaluation of individual differences between adults with ADHD remains therefore an important topic within the field of decision-making research. Furthermore, most studies focused on risky decision-making whereas other domains of decision-making (e.g., deliberative/analytic decision-making, social decision-making or FDM) were underrepresented in the included studies. Therefore, more research on decision-making in adults with ADHD other than risky decision-making is needed. The studies presented in chapters 7 and 8 further elaborate on the evaluation of decision- making in adults with ADHD and focus specifically on FDM capability. Both studies provide evidence that adults with a clinical number of current symptoms of ADHD (i.e., ≥ 5 symptoms of inattention and/or ≥ 5 symptoms of hyperactivity and impulsivity, as described in the Diagnostic and Statistical Manual of Mental Disorders edition 5, were present in the last six months) have more difficulties with several aspects of FDM capability in comparison to individuals without current symptoms of ADHD. The study presented in chapter 7 evaluated a group of clinically diagnosed adults with ADHD and found that 55.6% of the adults with ADHD performed more than 1.5 standard deviations below the mean of a healthy control group on one or more FDM tests or questionnaires; performances that can be classified as (very) low (Bouma et al., 2012). More specifically, lower performances of adults with ADHD were found on measures of financial knowledge and judgment (i.e., the Financial Competence Assessment Inventory and the Financial Decision-Making Interview) in comparison to the healthy control group. Both aspects of FDM are considered to be relatively fundamental aspects of FDM (Appelbaum et al., 2016) and problems on these aspects might reflect difficulties in everyday life, such as difficulties with budgeting, paying bills or with identifying and understanding financial information of own financial assets, a bank statement or a health insurance brochure. The results also indicate that adults with ADHD have a stronger tendency to buy on impulse and used more often an avoidant and a spontaneous decision style when making financial decisions compared to healthy controls. These results were confirmed in a study evaluating the relation between impulsive buying and the use of financial decision styles and current