Background: The aims of the present study are to investigate whether there are differences in health-related quality of life (HRQoL) between girls and boys in two different age groups, to study how much of children’s variance in HRQoL can be explained by common psychosomatic health symptoms, and to examine whether the same set of psychosomatic symptoms can explain differences in HRQoL, both between girls and boys and between older and younger school children.

Methods: A cross-sectional study was conducted of 253 children, 99 of ages 11-12 years (n=51 girls, n=48 boys) and 154 of ages 15-16 years (n=82 girls, n=72 boys), in Swedish schools. The KIDSCREEN-52 instrument, which covers 10 dimensions of HRQoL and additional questions about psychosomatic health symptoms, were used. Analyses of variance were conducted to investigate differences between the genders and age groups, and in interaction effects on the KIDSCEEN-52 dimensions. Regression analyses were used to investigate the impacts of psychosomatic symptoms on gender and age group differences in HRQoL.

Results: Boys rated themselves higher than girls on the KIDSCREEN dimensions: physical and psychological well-being, moods and emotions, self-perception, and autonomy. Main effects of age group were found for physical well-being, psychological well-being, moods and emotions, self-perception, autonomy, and school environment, where younger children rated their HRQoL more highly than those aged 15-16 years. Girls rated their moods and emotions dramatically lower than boys in the older age group, but the ratings of emotional status were more similar between genders at younger ages. Psychosomatic symptoms explained between 27% and 50% of the variance in the children’s HRQoL. Sleeping difficulties were a common problem for both girls and boys. Depression and concentration difficulties were particularly associated with HRQoL among girls whereas stomach aches were associated with HRQoL among boys.  

Conclusions: Girls and adolescents experience poorer HRQoL than boys and younger children, but having psychosomatic symptoms seem to explain a substantial part of the variation. Strategies to promote health among school children, in particular to alleviate sleep problems among all children, depression and concentration difficulties among girls, and stomach aches among boys, are of great importance.