Aims: To examine the development of self-assessed and parent proxy-assessed health related quality of life (HRQL) in pre-adolescent schoolchildren.
Methods: The population (n = 1,346) consisted of the total cohort of children starting 4th grade (age 10) in 2004 in primary schools in a Finnish city of 175,000 inhabitants. HRQL was assessed using the Pediatric Quality of Life Inventory 4.0 (PedsQL 4.0). The baseline study was conducted in 2004 (child age 10) and follow-up in a panel setting in 2006 (child age 12). The response rate for the children was 80% (n = 1,094) in 2004 and 85% (n = 1,139) in 2006. The response rate for children having responded both in 2004 and 2006 was 73% (n = 986). For parents of the children, one parent participated in the parents' survey (n = 999 in 2004, n = 888 in 2006).
Results: HRQL scores increased significantly in the two-year follow up (child t = 10.16-5.95, p < 0.0001, parent-proxy t = 6.35-2.76, p < 0.0001-0.006). Correlation between baseline and follow-up assessments was significant (child r = 0.4-0.5, p < 0.0001, parent r = 0.47-0.57, p < 0.0001). The correlation between baseline HRQL and change was negative (child r =-0.67 to -0.56, p < 0.0001, parent r =-0.62 to -0.46, p < 0.0001). Correlation between child and parent assessments increased from baseline (r = 0.20-0.39, p < 0.0001) to follow up (r = 0.3-0.42, p < 0.0001).
Conclusions: Child-assessed and parent proxy-assessed HRQL scores increase, suggesting HRQL improves, when children grow from age 10 to age 12. Baseline HRQL may not strongly predict future HRQL in early adolescence. The correlation between child self-assessment and parent proxy-assessment is fragile.