Table 4:

Correlation between category-based features and PHQ-9 scores.

		All		Depressed		Non-depressed
	Feature	r-value	p-value	r-value	p-value	r-value	p-value
iOS	Duration (social)	0.28	10−4	0.21	0.02	0.26	0.07
	Duration (mail)	−0.24	10−3	−0.29	10−3	−0.02	0.90
	Duration (video)	0.01	0.85	0.02	0.79	10−3	0.97
	Duration (audio)	−0.17	0.04	−0.12	0.23	−0.24	0.09
	Duration (gaming)	0.27	10−4	0.10	0.25	0.37	10−3
	Duration (shopping)	0.06	0.41	0.11	0.21	−0.03	0.85
	Duration (study)	−0.13	0.11	−0.08	0.42	−0.05	0.76
	Number of sessions (social)	0.25	10−3	0.34	10−4	0.12	0.37
	Number of sessions (mail)	−0.06	0.49	−0.11	0.28	0.13	0.33
	Number of sessions (video)	0.12	0.12	0.04	0.60	0.16	0.24
	Number of sessions (audio)	−0.06	0.49	0.04	0.65	−0.16	0.28
	Number of sessions (game)	0.33	10−6	0.37	10−5	0.27	0.04
	Number of sessions (shopping)	0.30	10−5	0.42	10−6	0.25	0.06
	Number of sessions (study)	0.10	0.19	0.17	0.05	0.10	0.47
Android	Duration (social)	0.20	0.27	0.13	0.56	0.26	0.47
	Duration (mail)	−0.09	0.62	−0.07	0.77	−0.2	0.58
	Duration (video)	0.44	0.01	0.28	0.20	0.74	0.01
	Duration (audio)	0.17	0.34	0.38	0.08	−0.31	0.38
	Duration (gaming)	0.52	10−3	0.17	0.44	0.65	0.04
	Duration (shopping)	−0.47	0.01	−0.49	0.02	−0.51	0.14
	Duration (study)	−0.27	0.12	−0.30	0.18	−0.16	0.67
	Number of sessions (social)	0.40	0.02	0.04	0.86	0.50	0.14
	Number of sessions (mail)	0.12	0.50	−0.22	0.33	0.42	0.22
	Number of sessions (video)	0.46	0.01	−0.49	0.02	0.64	0.05
	Number of sessions (audio)	−0.04	0.84	0.05	0.82	0.01	0.90
	Number of sessions (game)	0.65	10−5	0.02	0.91	0.86	10−3
	Number of sessions (shopping)	−0.24	0.18	−0.40	0.06	0.43	0.22
	Number of sessions (study)	−0.18	0.31	−0.40	0.06	0.42	0.22