There is a lack of consensus on the definition of a haemodynamic significant duct in RCTs, highlighting the need for standardized criteria to improve study comparability.
We found a wide variety in the definition of an HSDA. This finding implies that comparison of studies is difficult. International consensus should be reached on the definition of an HSDA, which will make future studies more comparable.
Zonnenberg et al. (2011) studied this question.