  The right ventricular (RV) function deterioration strongly predicts clinical
outcomes in numerous circumstances. To boost the clinical deployment of
ensemble regression methods that quantify RV volumes using tabular data from
the widely available two-dimensional echocardiography (2DE), we propose to
complement the volume predictions with uncertainty scores. To this end, we
employ an instance-based method which uses the learned tree structure to
identify the nearest training samples to a target instance and then uses a
number of distribution types to more flexibly model the output. The
probabilistic and point-prediction performances of the proposed framework are
evaluated on a relatively small-scale dataset, comprising 100 end-diastolic and
end-systolic RV volumes. The reference values for point performance were
obtained from MRI. The results demonstrate that our flexible approach yields
improved probabilistic and point performances over other state-of-the-art
methods. The appropriateness of the proposed framework is showcased by
providing exemplar cases. The estimated uncertainty embodies both aleatoric and
epistemic types. This work aligns with trustworthy artificial intelligence
since it can be used to enhance the decision-making process and reduce risks.
The feature importance scores of our framework can be exploited to reduce the
number of required 2DE views which could enhance the proposed pipeline's
clinical application.
