“…In 14 of these, the effect of the intervention on ADHD symptoms was assessed as secondary study outcomes, and in three of the studies, symptoms were measured for sample eligibility using the ADHD-RS-IV scales (Davis et al, 2018) and the SNAP-IV Scale (Hamidi et al, 2020;Kollins et al, 2020). Nine of the investigations reported positive effects of training on the reduction of ADHD symptoms (Barzegar et al, 2020;Bigorra et al, 2016;Bioulac et al, 2020;Bul et al, 2018;Kofler et al, 2018Kofler et al, , 2020Meyer et al, 2020;Nejati, 2020;Pahlevanian et al, 2017), while five studies reported that cognitive training based on computer systems does not lead to an improvement in ADHD symptoms (Bikic et al, 2018;Dentz et al, 2020;Dovis et al, 2019;Lee et al, 2021;Smith et al, 2020).…”