Abstract: Four studies (involving 206 participants) met the inclusion criteria for this review. Three studies, involving 194 participants, assessed the effects of online interventions to target executive functioning (that is monitoring and changing behaviour, problem solving, planning, etc.). These studies, which were all conducted by the same research team, compared online interventions against a 'placebo' (participants were given internet resources on brain injury). The interventions were delivered in the family home with additional support or training, or both, from a psychologist or doctoral student. The fourth study investigated the use of a computer program to target memory in addition to components of executive functioning (that is attention, organisation, and problem solving). No information on the study setting was provided, however a speech-language pathologist, teacher, or occupational therapist accompanied participants. Two studies assessed adolescents and young adults with mild to severe traumatic brain injury (TBI), while the remaining two studies assessed children and adolescents with moderate to severe TBI. Risk of bias We assessed the risk of selection bias as low for three studies and unclear for one study. Allocation bias was high in two studies, unclear in one study, and low in one study. Only one study (n = 120) was able to conceal allocation from participants, therefore overall selection bias was assessed as high. One study took steps to conceal assessors from allocation (low risk of detection bias), while the other three did not do so (high risk of detection bias). Primary outcome 1: Executive functioning: Technology-based intervention versus placebo Results from meta-analysis of three studies (n = 194) comparing online interventions with a placebo for children and adolescents with TBI, favoured the intervention immediately post-treatment (standardised mean difference (SMD) -0.37, 95% confidence interval (CI) -0.66 to -0.09; P = 0.62; I2 = 0%). (As there is no 'gold standard' measure in the field, we have not translated the SMD back to any particular scale.) This result is thought to represent only a small to medium effect size (using Cohen’s rule of thumb, where 0.2 is a small effect, 0.5 a medium one, and 0.8 or above is a large effect); this is unlikely to have a clinically important effect on the participant. The fourth study (n = 12) reported differences between the intervention and control groups on problem solving (an important component of executive functioning). No means or standard deviations were presented for this outcome, therefore an effect size could not be calculated. The quality of evidence for this outcome according to GRADE was very low. This means future research is highly likely to change the estimate of effect. Primary outcome 2: Memory One small study (n = 12) reported a statistically significant difference in improvement in sentence recall between the intervention and control group following an eight-week remediation programme. No means or standard deviations were presented for this outcome, therefore an effect size could not be calculated. Secondary outcomes Two studies (n = 158) reported on anxiety/depression as measured by the Child Behavior Checklist (CBCL) and were included in a meta-analysis. We found no evidence of an effect with the intervention (mean difference -5.59, 95% CI -11.46 to 0.28; I2 = 53%). The GRADE quality of evidence for this outcome was very low, meaning future research is likely to change the estimate of effect. A single study sought to record adverse events and reported none. Two studies reported on use of the intervention (range 0 to 13 and 1 to 24 sessions). One study reported on social functioning/social competence and found no effect. The included studies reported no data for other secondary outcomes (that is quality of life and academic achievement). This review provides low-quality evidence for the use of technology-based interventions in the rehabilitation of executive functions and memory for children and adolescents with TBI. As all of the included studies contained relatively small numbers of participants (12 to 120), our findings should be interpreted with caution. The involvement of a clinician or therapist, rather than use of the technology, may have led to the success of these interventions. Future research should seek to replicate these findings with larger samples, in other regions, using ecologically valid outcome measures, and reduced clinician involvement.

Plain-language summary: We identified four studies (including 206 participants) that investigated the effectiveness of technology-based interventions to rehabilitate children and adolescents with traumatic brain injury. All four studies were conducted in North America, with three originating from the same research team. One study with 120 participants used an online Counselor-Assisted Problem Solving (CAPS) intervention to rehabilitate executive functioning in adolescents aged 12 to 17 years. One study with 35 participants used a Teen Online Problem-Solving intervention to target the executive functioning of adolescents aged 11 to 18 years. One study with 40 participants used an online Family Problem Solving intervention to target outcomes such as behaviour and aspects of executive functioning in children aged 5 to 16 years. One study with 12 participants used a computer program to target cognitive-communication skills including memory and aspects of executive functions in adolescents and young adults aged 12 to 21 years. All funding sources were in the USA or Canada. One study was funded by the Colorado Department of Human Services and two National Institutes of Health (NIH) awards. A second study was also funded by a NIH grant. One study was funded by a hospital charity in addition to the Easter Seal Research Institute and Apple Canada. The final study was supported by the Ohio Department of Safety. This review found evidence that interventions employing technological aids did improve executive functions in adolescents with traumatic brain injury (i.e. a brain injury resulting from a road traffic accident, fall, or blow to the head). However, this result was relatively modest and is unlikely to have a clinically important effect on the child. One study employed technology to improve memory in adolescents with TBI and showed an improvement for the intervention group. It was not possible to determine how effective this approach was as the study failed to include adequate statistical information. Two studies examined the secondary outcomes of anxiety and depression but did not show any effect between the intervention and control groups at 6 months follow-up. Only one study recorded adverse events, and reported that none occurred. Two studies reported on the amount of use the intervention received. One study reported improvements in social functioning/social competence for the intervention group. No data were reported which related to the review's other secondary outcomes. We found the quality of evidence for all outcomes to be low, which means future research is likely to change the estimate of effect. All four studies were small, and it was not always possible to conceal group allocation to participants. Three studies failed to conceal group allocation to those who measured the outcomes.