We have read with great interest the recent editorial by Pellegrini et al. Undoubtedly, now more than ever, we have begun to question the true role of tidal volume (VT) in acute respiratory distress syndrome (ARDS).

As well described, there are two questions that remain unanswered, and we believe that these questions are even more complex than it seems and should be approached from a different perspective.

From a statistical perspective, VT represents a continuous variable with an infinite range of values.

When such variables are dichotomized (binary variable) (6 ml vs 10 ml predicted body weight), statistical information is lost (statistical entropy increases).

In other words, when estimating the mean of a binary variable derived from an underlying continuous variable, in most cases the information about the continuous variable is not utilized, and the estimation is simply carried out using the derived binary variable.

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