TABLE 5.

Associations of variables with C-SDS score (n = 1002).

	Mean (SD) C-SDS score	b [95% CI]	p
Sex
Female	49.78 (8.23)	Ref.
Male	48.12 (8.96)	–1.65 [–2.73, –0.58] **	p = 0.003
Age		–0.12 [–0.47,0.22]	p = 0.486
Freshman	49.23 (8.56)	Ref.
Sophomore	48.96 (8.27)	–0.26 [–1.75,1.23]	p = 0.729
Junior	49.09 (8.92)	–0.14 (–1.75,1.23)	p = 0.834
Senior	48.81 (8.35)	–0.42 (–2.35,1.52)	p = 0.675
Postgraduate	50.50 (7.76)	1.27 (–1.86,4.41)	p = 0.426
The purpose of using a smartphone
Non- instant messaging	48.89 (8.46)	Ref.
Instant messaging	49.65 (8.80)	0.76 [–0.40,1.92]	p = 0.198
Non-social media	46.40 (9.17)	Ref.
Social media	49.53 (8.40)	3.13 [1.57,4.69] ***	p < 0.001
Non-music	48.28 (8.59)	Ref.
Music	49.42 (8.54)	1.14 [–0.06, 2.34]	p = 0.062
Non-game	48.79 (8.44)	Ref.
Game	49.68 (8.77)	0.88 [–0.22, 1.98]	p = 0.116
Non-shopping	48.58 (8.43)	Ref.
Shopping	50.00 (8.73)	1.42 [0.33,2.51] *	p = 0.011
Non-learning	49.54 (8.54)	Ref.
Learning	48.48 (8.57)	–1.06 [–2.14, 0.02]	p = 0.054
Time on smartphone (hours per day)
< 3h	45.21 (7.37)	Ref.
≥ 3 and < 9h	48.35 (8.38)	3.14 [0.39,5.89] *	p = 0.025
≥9h	51.66 (8.64)	6.45 [3.59,9.31] ***	p < 0.001
FoMO		0.40 [0.34,0.46] ***	p < 0.001
SAS-SV		0.66 [0.61,0.71] ***	p < 0.001
MSUQ-PM		0.53 [0.47,0.59] ***	p < 0.001
MSUQ-NM		0.73 [0.65,0.80] ***	p < 0.001

SD = Standard deviation; CI = Confidence interval; *p < 0.05. **p < 0.01. ***p < 0.001.