From:  Explainable AI for multi-omics in precision medicine: a systematic review

 Key challenges and future research directions.

Challenge categorySpecific challengeCurrent limitationFuture directionKey references
Data characteristicsHigh dimensionalityOverfitting; unstable feature selection; curse of dimensionalitySelf-supervised learning; foundation models; synthetic data generation[6, 8]
Data heterogeneityIntegration difficulty; modality-specific characteristics lostAdvanced fusion strategies; modality-specific encoders with shared representations[9, 40]
Batch effectsConfounded models; poor generalizationStandardized preprocessing; robust normalization; batch-invariant representations[14, 75]
Missing modalitiesIncomplete data; biased imputationMasked modeling; generative imputation; modality-agnostic architectures[15, 53]
MethodologicalInterpretability vs. performance trade-offBlack-box models outperform interpretable onesHybrid models; intrinsically interpretable architectures; attention mechanisms[19, 22]
Explanation faithfulnessPost-hoc explanations may not reflect model behaviorFaithfulness benchmarks; causal explanation methods; model-specific XAI[21, 45]
ScalabilityComputational cost of training and explaining large modelsEfficient attention; sparse architectures; federated learning[108, 109]
EvaluationLack of standardized benchmarksInconsistent evaluation; incomparable resultsCommunity benchmarks (e.g., MOB); standardized metrics for XAI[42, 50]
ReproducibilityVariability in preprocessing, splits, seedsOpen code; shared pipelines; reproducible workflows[14, 73]
Clinical validationFew prospective studies; limited external validationMulti-center trials; real-world evidence; regulatory pathways[34, 60]
TranslationalWorkflow integrationModels not integrated with EHR/clinical systemsInteroperability standards (HL7 FHIR); user-centered design[29, 35, 97]
Regulatory approvalUnclear pathways for AI as medical deviceEngage regulators early; validation frameworks; post-market surveillance[18]
Ethical and fairness concernsBias in training data; privacy risksFederated learning; fairness audits; inclusive cohort design[32, 60]
Emerging frontiersCausal inferenceCorrelation-based predictions limit mechanistic insightCausal AI; Mendelian randomization; interventional predictions[14, 110]
Foundation modelsLimited pre-trained models for multi-omicsMulti-modal foundation models; transfer learning; open-source models[108, 111]
Digital twinsNo integrated patient simulationsMulti-modal digital twins; generative models; personalized simulations[112, 113]
Human-in-the-loopAI decisions without clinician oversightInteractive XAI; clinician feedback loops; collaborative AI[32, 33]

XAI: explainable artificial intelligence.