How young can children reliably and validly self-report their health-related quality of life?: An analysis of 8,591 children across age subgroups with the PedsQL™ 4.0 Generic Core Scales

Table 6 PedsQL™ 4.0 Generic Core Scales School Functioning Scale Score: Child Self-Report Reliability and Validity

Age	Reliability		Validity
			Chronic Health Condition				Healthy Sample
	n	α	Mean	SD	% Floor	% Ceiling	Mean	SD	% Floor	% Ceiling	Chronic vs. Healthy Difference	Chronic vs. Healthy Effect Size
5 yrs	702	0.63	72.24	20.78	0.0	13.5	82.02	15.92	0.0	22.5	9.77*	0.61
6 yrs	920	0.59	71.81	18.11	0.0	10.5	79.93	16.56	0.1	21.6	8.12*	0.49
7 yrs	873	0.62	68.15	18.15	0.0	5.4	77.90	17.16	0.0	18.4	9.76*	0.57
8 yrs	872	0.68	73.27	17.39	0.0	6.7	82.11	15.56	0.0	21.0	8.84*	0.57
9 yrs	831	0.74	69.75	19.59	0.0	5.1	81.05	17.15	0.4	18.1	11.30*	0.66
10 yrs	832	0.72	72.76	19.45	0.4	8.9	80.95	16.32	0.0	19.4	8.19*	0.50
11 yrs	676	0.76	72.37	19.37	0.4	7.7	83.43	15.56	0.0	23.8	11.05*	0.71
12 yrs	677	0.75	71.94	19.30	0.4	8.4	80.25	17.26	0.0	20.5	8.30*	0.48
13 yrs	612	0.79	69.56	21.34	0.0	8.9	80.17	17.13	0.0	19.3	10.61*	0.62
14 yrs	563	0.76	69.94	18.14	0.0	8.4	81.17	17.07	0.3	21.9	11.23*	0.66
15 yrs	556	0.78	67.78	19.02	0.0	5.2	79.33	17.85	0.0	20.8	11.55*	0.65
16 yrs	328	0.77	68.36	19.93	0.6	5.6	81.49	17.41	0.0	23.0	13.12*	0.75

Note: Total N = 8,442 for reliability, Total N = 8,211 for validity.
Higher values equal better health-related quality of life.
% Floor/Ceiling = the percentage of scores at the extremes of the scaling range.
Effect sizes are designated as small (.20), medium (.50), and large (.80).
*p < .001 (independent samples t-test).

ISSN: 1477-7525