“…The recent literature on time trends in asthma shows the large use of the comparison between stages I and III of ISAAC, 2,5,11,15,16,20 which observed this prevalence in the six-and-seven-year age group, in the 13-and-14-year age group, or in both. However, the majority of these studies were performed in Europe and Asia; only three of these were conducted in Latin America, of which one was in Chile 11 and two in Brazil.…”