A survey study of the association between mobile phone use and daytime sleepiness in California high school students

Table 3 Multivariate model

	Value	SE	t-value	p-value
Intercept	9.05	0.860	10.5	<;0.0001
Sex	0.798	0.258	3.09	<;0.01
Accessible - never	−4.09	2.49	−1.64	0.10
Accessible - now and then	−1.98	1.07	−1.85	0.066
Accessible - daily	−2.04	0.910	−2.24	<;0.05
Accessible - all day	−2.58	0.958	−2.69	<;0.01
Reduce use?	0.659	0.317	2.08	<;0.05

Final model predicting ESS. Sex was coded as male = −1, female = 1; For accessibility, “Accessible – around the clock” was used as a reference category and each category was scored as yes = 1, blank = 0; Reduce use? was coded as yes = 1, no = −1.

ISSN: 1471-2458