Multi-label clinical document classification: Impact of label-density.

•Expert clinicians assign, manually, codes from the ICD-10 to health records.•Neural Networks (NNs) are well suited for multi-label classication tasks.•Challenges: infer models from data with low label-density and capture dependencies.•Experiments: three NNs with label-consistency rectification on two corpora.•Contribution: (1) show dependence of performance on label density (2) release software.