“…All the studies specified the intervention age, except for one ( 33 ), which only made reference to the age of the preterm group. Considering the last condition, it may be observed that seven studies were carried out during the first year of life of the participants ( 18 – 22 , 29 , 32 , 33 ), six were carried out from 3 to 10 years old ( 23 , 24 , 26 , 30 , 31 ), two were developed at the age of 13–17 years old ( 25 , 27 , 28 ) and one was carried out during the first year of life of the preterm infants group, but here the age of the control group was not specified ( 33 ). Out of the 16 studies included, six followed the evolution of the participants during a determined period of time; four were of a prospective nature ( 18 , 20 – 22 ), and two of a retrospective nature ( 32 , 33 ); the rest were cross-sectional studies.…”