Table 2.

Comparison between participants with complete and incomplete datasets

	Completeness	N	Mean	t	p
Age 7 SDQ	1.00	5251	3.22	− 5.69	< 0.001
	0.00	1120	3.67
Age 14 SDQ	1.00	5251	2.93	− 3.90	< 0.001
	0.00	116	3.81
Sedentary behavior	1.00	5251	390.61	− 0.75	0.455
	0.00	1257	392.21
Light activity	1.00	5251	281.06	− 0.57	0.566
	0.00	1257	281.81
Moderate activity	1.00	5251	42.83	− 3.83	<0.001
	0.00	1257	44.47
Vigorous activity	1.00	5251	20.01	− 1.16	0.247
	0.00	1257	20.41
Month of birth	1.00	5251	6.43	− 0.76	0.448
	0.00	1257	6.51
Sex	1.00	5251	1.50	0.69	0.490
	0.00	242	1.48
NVQ highest academic level (all sweeps)	1.00	4725	3.21	1.47	0.14
	0.00	142	3.07
OECD equalized income	1.00	5190	400.09	9.29	< 0.001
	0.00	1242	332.91

Independent t tests between participants with complete and incomplete datasets; 1 = complete dataset, 0 = incomplete dataset