Table 1.

Participants’ characteristics (N=66).

Characteristics		Values
Age (years), mean (SD)		33.7 (3.7)
Birth history, n (%)
	Primipara	26 (39)
	Multipara	40 (61)
Educational background, n (%)
	High schools	6 (9)
	Junior college or professional school	29 (44)
	University or graduate school	31 (47)
Job type, n (%)
	Professional and technical	32 (48)
	Clerical	20 (30)
	Sales, service, agriculture, production, and construction	14 (21)
Employment status, n (%)
	Full-time	54 (82)
	Part-time	12 (18)
Smartphone use time (hours per day)a, n (%)
	<2	23 (37)
	2-3	17 (27)
	>3	22 (36)

^aWith missing data (n=62).