Are There any Possible Side Effects of Neurofeedback? A Systematic Literature Review and Meta-analysis

Context: This study aimed to investigate the pieces of evidence related to the possible side effects of neurofeedback (NFB) for individuals suffering from attention-deficit hyperactivity disorder (ADHD) and epilepsy. In this systematic review of randomized controlled trials (RCTs) for individuals suffering from these two conditions, several databases were investigated. Evidence Acquisition: To achieve this goal, the table of the first outcomes was to rate the symptoms of epilepsy based on the evaluation of patients. CANTAB (Cambridge Neuropsychological Test Automated Battery), Wechsler Intelligence Scale for Children II (WISC II), and attention span test. Additionally, side effects were assessed by ADHD and epilepsy side effect checklists. Among the documents, 17 of them had the criteria to be included. Results: It was a randomized effect model that was used to evaluate the pooled prevalence of side effects with confidence intervals (CI) of 95%. Moreover, in Stata software (version 14), a Metaprop command was deployed. The approximate pooled prevalence of the side effects was 0.05 (95% CI: 0.03 - 0.08). To measure heterogeneity among studies, I2 statistics and the Galbraith diagram were applied. I2 statistics were estimated as 2.34%, and the Galbraith diagram did not indicate any heterogeneity. The univariate meta-regression (UMR) model showed despite a decreasing trend, the results were not statistically significant. Conclusions: It could be inferred from the results that preliminary evidence is that NFB is a non-invasive treatment and a more beneficial clinical method. It is proposed that to compare standard treatments, such as medication, neurological, and behavioral interventions, further RTCs are required.