. 2019 Sep 26;34(41):e263. doi: 10.3346/jkms.2019.34.e263

Table 5. Changes in time of media use from Wave 1 to Wave 3 stratified by sex.

Variables			Wave 1	Wave 2	Wave 3	P value	Post hoc analysis
Girls
	TV
		Weekday	1.4 (0.1)	1.6 (0.1)	1.8 (0.2)	< 0.001^a	1 < 3
		Weekend	1.9 (0.2)	2.5 (0.2)	2.6 (0.2)	< 0.001^a	1 < 2,3
	Tablet PC
		Weekday	0.7 (0.1)	1.0 (0.2)	1.2 (0.2)	< 0.05^b	1 < 3
		Weekend	0.9 (0.2)	1.5 (0.3)	1.5 (0.3)	< 0.05^b	1 < 2,3
	Smartphone
		Weekday	0.5 (0.1)	0.7 (0.1)	0.9 (0.1)	< 0.001^a	1 < 3
		Weekend	0.8 (0.1)	1.1 (0.1)	1.3 (0.1)	< 0.001^a	1 < 2,3
Boys
	TV
		Weekday	1.5 (0.1)	2.1 (0.2)	2.3 (0.2)	< 0.001^a	1 < 2,3
		Weekend	2.2 (0.2)	2.7 (0.2)	2.9 (0.2)	< 0.001^a	1 < 2,3
	Tablet PC
		Weekday	0.8 (0.2)	0.9 (0.2)	1.5 (0.3)	< 0.001^a	1,2 < 3
		Weekend	0.8 (0.1)	1.1 (0.2)	1.8 (0.3)	< 0.001^a	1 < 3
	Smartphone
		Weekday	0.7 (0.1)	0.9 (0.1)	1.3 (0.1)	< 0.001^a	1,2 < 3
		Weekend	1.1 (0.1)	1.3 (0.1)	1.5 (0.1)	< 0.05^b	1 < 3

Data are represented as mean ± standard deviation and analyzed by Friedman test followed by Wilcoxon signed rank test at post-hoc analysis.

^aCorrected P < 0.01; ^bcorrected P < 0.05