Table 3.

Quantitative overlap checks and partitioning strategy used in model training and evaluation.

Check	Definition	Result
Exact duplicate overlap	Number of validation samples that exactly matched a training sample	0
High-similarity overlap	Number of the first 100 checked validation samples with cosine similarity > 0.99 to any training sample	0/100
Holdout split strategy	Method used to create the holdout set	10% class-stratified sample-level split
Cross-validation split strategy	Method used to create CV folds	3-fold stratified by breathing class