Radiomics vs Deep Learning in Autism Classification Using Brain MRI: A Systematic Review

Autism diagnosis through magnetic resonance imaging (MRI) has advanced significantly with the application of artificial intelligence (AI). This systematic review examines three computational paradigms: radiomics-based machine learning (ML), deep learning (DL) and hybrid models combining both. Across 49 studies (2011-2025), radiomics methods relying on classical classifiers (i.e. SVM, Random Forest), achieved moderate accuracies (61-89%) and offered strong interpretability. DL models, particularly convolutional and recurrent neural networks applied to resting-state functional MRI, reached higher accuracies (up to 98.2%) but were hampered by limited transparency and generalizability. Hybrid models combining handcrafted radiomic features with learned DL representations via dual or fused architectures demonstrated promising balances of performance and interpretability, but remain underexplored. A persistent limitation across all approaches is the lack of external validation and harmonization in multi-site studies, which affects robustness. Future pipelines should include standardized preprocessing, multimodal integration, and explainable AI frameworks to enhance clinical viability. This review underscores the complementary strengths of each methodological approach while hybrid approaches appear as a promising middle ground of improved classification performance and enhanced interpretability.