Both Individual and Group-Based Neuropsychological Interventions of Dyslexia Improve Processing Speed in Young Adults: A Randomized Controlled Study

Validation and Reliability of the Dyslexia Adult Checklist in Screening for Dyslexia

Dyslexia is a language-based neurobiological and developmental learning disability marked by inaccurate and disfluent word recognition, poor decoding, and difficulty spelling. Individuals can be diagnosed with and experience symptoms of dyslexia throughout their lifespan. Screening tools such as the Dyslexia Adult Checklist allow individuals to self-evaluate common risk factors of dyslexia prior to or in lieu of obtaining costly and timely psychoeducational assessments. Although widely available online, the Dyslexia Adult Checklist has yet to be validated. The purpose of this study was to validate this Checklist in a sample of adults with and without dyslexia using both univariate and multivariate statistical approaches. We hypothesised that the Dyslexia Adult Checklist would accurately distinguish between individuals with a self-reported diagnosis of dyslexia (n = 200) and a control group (n = 200), as measured by total scores on the screening tool. Results from our sample found the Dyslexia Adult Checklist to be valid (Cronbach's α = 0.86), and reliable (sensitivity = 76%-91.5%, specificity = 80%-88%). Compared to the originally proposed cut-off score of 45, given the higher sensitivity rate and negative predictive value, we recommend researchers and clinicians use a cut-off score of 40 to indicate possible mild to severe symptoms of dyslexia when using the Dyslexia Adult Checklist.

Goal attainment in individual and group-based neuropsychological interventions for young adults with dyslexia in a randomized controlled trial

In this study, we investigated the outcome of goal attainment in individual and group-based neuropsychological intervention for young adults with dyslexia. Participants (N = 120) were randomly assigned to individual intervention, group intervention, or wait-list control group. Attainment of goals set personally before the intervention was evaluated after the intervention using Goal Attainment Scaling. The participants were asked to report the number of concrete changes made in their study or working habits at five months (after intervention or wait-list control time), at ten months, and 15 months post-interventions. Potential predictive factors for predicting goal attainment were evaluated including background and cognitive variables, self-reported psychological variables (mood, cognitive and behavioral strategies, self-esteem, quality of life), and self-reported behavioral variables (concrete changes made, time used to work on intervention matters). Based on the results, personal goals were, on average, met especially in individual intervention. Nearly 50% of goal attainment was explained by intervention type, behavioral and cognitive strategies, concrete changes made, cognitive capacity, and used time. Concrete changes, e.g., adopting new strategies and methods in study or working habits, were reported in both interventions and more than during the wait-list control period. The changes seemed long-lasting as fifteen months post-intervention, 76.4% reported still using the learned strategies. A structured and relatively short neuropsychological intervention for dyslexia in either individual or group format can lead to attaining pre-set personal goals and positive behavioral changes that can last up to over a year post-intervention.

Neuropsychological intervention of dyslexia has a positive effect on aspects of psychological well-being in young adults - a randomized controlled study

Effectiveness of individual- and group-based neuropsychological intervention on aspects of psychological well-being of dyslexic adults was evaluated. Dyslexic young adults (n = 120) were randomly assigned into individual intervention, group intervention or wait-list control group. Both interventions focussed on cognitive strategy learning, supporting self-esteem, and using psychoeducation. In group format peer support was also utilized. Cognitive and behavioural strategies, mood states, quality of life and self-esteem were assessed via self-report questionnaires at baseline, after the intervention/wait-list control time at 5 months and 10 months. Results indicated that the neuropsychological interventions had a positive effect on self-evaluated cognitive and behavioural strategies, especially in increasing success expectations and to a lesser degree in diminishing task-avoidance and in group intervention in diminishing social pessimism. The interventions also improved cognition-related quality of life and, to a lesser degree, self-esteem. These results indicate that structured neuropsychological interventions can positively affect self-evaluated psychological well-being, especially on cognitive and behavioural strategies. Considering the secondary consequences of dyslexia, support among young adults is often needed beyond the cognitive and reading-based challenges dyslexia poses.

The use of noninvasive brain stimulation techniques to improve reading difficulties in dyslexia: A systematic review

Noninvasive brain stimulation (NIBS) allows to actively and noninvasively modulate brain function. Aside from inhibiting specific processes, NIBS may also enhance cognitive functions, which might be used for the prevention and intervention of learning disabilities such as dyslexia. However, despite the growing interest in modulating learning abilities, a comprehensive, up-to-date review synthesizing NIBS studies with dyslexics is missing. Here, we fill this gap and elucidate the potential of NIBS as treatment option in dyslexia. The findings of the 15 included studies suggest that repeated sessions of reading training combined with different NIBS protocols may induce long-lasting improvements of reading performance in child and adult dyslexics, opening promising avenues for future research. In particular, the "classical" reading areas seem to be most successfully modulated through NIBS, and facilitatory protocols can improve various reading-related subprocesses. Moreover, we emphasize the need to further explore the potential to modulate auditory cortex function as a preintervention and intervention approach for affected children, for example, to avoid the development of auditory and phonological difficulties at the core of dyslexia. Finally, we outline how future studies may increase our understanding of the neurobiological basis of NIBS-induced improvements in dyslexia.

Remote Neuropsychological Intervention for Developmental Dyslexia with the Tachidino Platform: No Reduction in Effectiveness for Older Nor for More Severely Impaired Children

Tachidino is a web-platform for remote treatment of reading and writing disorders. A total of 91 children with developmental dyslexia and/or dysorthographia participated in the present study and received Tachidino treatment. The purpose of the study was to compare results obtained after four weeks treatment and a six-month follow-up in older versus younger children and in more versus less severely impaired children (separately subdividing them according to reading speed, reading accuracy, and writing accuracy). The results showed no difference in improvement for reading accuracy and speed in the three age groups, but children below 9 years improved more than older children in writing accuracy. Regarding severity groups, children with more severe initial impairments improved more than children with less severe impairments. Additionally, the results were confirmed after controlling for spurious effects due to use of Z-scores and regression to the mean. The findings are discussed in terms of their theoretical and practical implications.

Dyslexia treatment studies: A systematic review and suggestions on testing treatment efficacy with small effects and small samples

Poor response to treatment is a defining characteristic of reading disorder. In the present systematic review and meta-analysis, we found that the overall average effect size for treatment efficacy was modest, with a mean standardized difference of 0.38. Small true effects, combined with the difficulty to recruit large samples, seriously challenge researchers planning to test treatment efficacy in dyslexia and potentially in other learning disorders. Nonetheless, most published studies claim effectiveness, generally based on liberal use of multiple testing. This inflates the risk that most statistically significant results are associated with overestimated effect sizes. To enhance power, we propose the strategic use of repeated measurements with mixed-effects modelling. This novel approach would enable us to estimate both individual parameters and population-level effects more reliably. We suggest assessing a reading outcome not once, but three times, at pre-treatment and three times at post-treatment. Such design would require only modest additional efforts compared to current practices. Based on this, we performed ad hoc a priori design analyses via simulation studies. Results showed that using the novel design may allow one to reach adequate power even with low sample sizes of 30–40 participants (i.e., 15–20 participants per group) for a typical effect size of d = 0.38. Nonetheless, more conservative assumptions are warranted for various reasons, including a high risk of publication bias in the extant literature. Our considerations can be extended to intervention studies of other types of neurodevelopmental disorders.

Psychosocial Interventions for the Enhancement of Psychological Resources among Dyslexic Adults: A Systematic Review

Dyslexic employees are likely to be more at risk of low levels of personal resources because of their cognitive makeup compared to their non-dyslexic counterparts. Low personal resources, in turn, may lead to low employability because of difficulties in positively facing transitions. This research aimed to systematically review evidence on interventions for improving psychological resources in dyslexic adults. We searched Scopus, ERIC EBSCOhost, PsycINFO, Social Science Citation Index Web of Science, and Universe up to May 2020. We also examined the reference lists of published studies. We included studies that compared any intervention format against no intervention, any other intervention considered as a comparator by the authors, or that had no control group. Participants were dyslexic adults aged minimum 18 years old. We included four studies with 278 participants. Studies were run in the UK, Sweden, and Finland. Two studies involved a control group, and two studies were observational. Interventions varied between studies in intensity, duration, and format (individual and small groups). Risk of bias was unclear for most risk criteria. Findings from this review show that there is initial evidence suggesting initiatives can be effective in supporting a set of personal resources, i.e., self-confidence, organization, time, and stress-management, which are important in allowing dyslexic adults’ positive adjustment in the workplace. Yet, more studies are needed to improve outcome assessment and study design.