Table 1.

Subject characteristics by age and sex

Age group	8–11 years old				12–18 years old
Sex	Boys (n = 357)		Girls (n = 416)		Boys (n = 408)		Girls (n = 383)
Respondents	321	89.9a	394	94.7	232	56.9	327	85.8
Respondents without missing values	244	76.0b	303	72.8	214	92.2	297	90.8
Age , years; mean, S.D.	9.2	0.9	9.2	0.9	14.4	1.7	14.6	1.6
Subjects with chronic illness	16	6.6c	18	5.9	14	6.5	23	7.7

	Mean	SD	Mean	SD	Mean	SD	Mean	SD
J-KIDSCREEN-52
Physical Well-being	58.8	12.5	57.9	12.0	49.7	11.8	49.0	12.1
Psychological Well-being	53.6	11.9	56.8*	10.9	45.9	11.9	48.9*	13.1
Moods & Emotions	52.0	11.6	53.6	11.8	47.2	10.9	47.7	12.0
Self-Perception	49.4	9.5	49.5	9.7	45.0	7.2	43.7	8.9
Autonomy	49.2	11.8	50.2	11.4	45.3	9.7	47.4*	10.2
Parent Relations & Home Life	51.3	10.9	53.6*	11.0	45.0	11.0	49.0*	12.1
Financial Resources	44.4	13.0	46.2	12.4	48.2	9.5	50.8*	9.8
Social Support & Peers	54.0	12.	57.6*	12.0	50.5	12.1	55.3*	12.9
School Environment	58.3	11.6	60.1	11.3	49.6	10.0	51.5*	10.8
Social Acceptance (Bullying)	47.6	12.2	48.7	11.1	44.8	11.8	47.4*	11.0
PedsQL
Physical functioning	92.7	10.1	91.4	11.4	93.1	11.8	92.8	10.2
Emotional functioning	86.7	16.9	85.0	19.3	89.8	15.5	86.4*	18.4
Social functioning	92.1	14.8	92.4	15.9	94.1	14.0	92.4	14.8
School functioning	90.2	12.5	91.1	13.7	89.5	13.9	87.7	15.0

* Statistically significant difference (p < 0.05) of mean scores noted between boys and girls in each age group by t test

^aPercentage of all respondents

^bPercentage of respondents without missing values

^cPercentage of subjects with chronic illness