Figure 1

IgA serum levels in function of age of the volunteers from the 3 countries. Results are presented as means ± SEM. Two-way ANOVA was performed to discriminate among the two factors age-group, country and their interaction followed by a post-hoc Newman-Keuls test. A significant age group-related effect was observed independently of the country-related factor. Means sharing different superscript letters are significantly different: a≠b≠c, p < 0.05.