Limitations
This review has a few limitations regarding the material and methods and
available evidence. First of all, there was a high heterogeneity between
the included studies in terms of population, type of disease, which
inequality was being addressed and outcome, making it difficult to group
these studies and draw definite conclusions. Moreover, because various
outcome measures were used it was not always possible to obtain
objective or numerical results and therefore subjective interpretation
may have taken place. Finally, bias might have occurred due to the
publication of studies which showed an effect of socioeconomic, ethnic
or environmental inequalities on PICU outcome.