Impact of Neurofibromatosis Type 1 on Executive Functions: A Meta-Analysis Based on the Use of the BRIEF

Objective: To determine whether executive function impairment is a defining feature in individuals with Neurofibromatosis Type 1 (NF1), through the analysis of assessments conducted using the BRIEF questionnaire. Design: Systematic review and meta-analysis focused on the evaluation of executive functions using the BRIEF instrument in individuals diagnosed with NF1. Data Sources: Studies gathered from relevant academic databases that used BRIEF or BRIEF-P to assess executive functions in populations with NF1. Study Selection: Included studies evaluated executive functions in individuals with a clinical diagnosis of NF1 using BRIEF, as reported by parents and teachers, and provided statistically analyzable effect sizes. Data Extraction: Effect sizes (Cohen's d) were collected and analyzed across various BRIEF scales, including clinical indices and global executive function indices. Results: Moderate to high executive deficits were observed in individuals with NF1 in areas such as Self-Monitoring, Working Memory, Initiative, Monitoring, Planning/Organization, and in the general indices of Metacognition and Behavioral Regulation, with effect sizes ranging from 0.658 to 1.031. No significant deficits were found in the Flexibility scale. Parent and teacher evaluations revealed moderate executive deficits (d = 0.494–0.625). Deficits were higher when assessed with BRIEF compared to BRIEF-P (d = 0.381–0.815). Conclusions: Executive function impairment is a significant feature in individuals with NF1, particularly in behavioral regulation and metacognition domains, as evidenced by BRIEF assessments.