Uncertainty analysis of feature extraction from expired gas traces

Non invasive medical analyses are a convenient method to study several pathologies and determine important health `indicators', even though an estimation of the indicator uncertainty is often difficult to obtain. The usefulness of such indicators depends on the employed model, but also on the uncertainty that is connected with the indicator determination. This paper deals with the problems related to the estimation of the uncertainty when the indicators are computed by means of a non trivial processing on recorded traces of clinical parameters. The paper is focused on the analysis of expired gas traces, but the procedure can be applied in many other cases where the processing involves the manual or automatic selection on suitable `key points' on repetitive traces.