Table 3.

Associations Between Questionnaire and Sensor Data

Questionnaire	Sensor Measure	Unadjusted β Coefficient (95% CI)	PValue	Adjusted β Coefficient (95% CI)	PValue
CES-D = Center for Epidemiologic Studies–Depression; CI = confidence interval; MCS = mental component score; PCS = physical component score; SF-36 = 36-Item Short Form Health Survey; YPAS = Yale Physical Activity Survey.
Notes: Questionnaire is the dependent variable, and sensor measure is the independent variable. Speaking, stationary, walking flat, walking up, and walking down are percentages of time spent in those activities.
^a Adjusted for age and sex.
^b Adjusted for age, sex, marital status, and pet ownership.
^c Weighted using the following weights: 0.6 for stationary, 3 for walking level, 5 for walking up, 1 for walking down, and −1.5 for unclassified.
Behavior
SF-36 MCS	Speaking	1.29 (−0.46 to 2.62)	.055	1.14 (−0.36 to 2.65)^a	.08
CES-D	Speaking	−1.14 (−2.42 to 0.13)	.07	−1.23 (−2.38 to −0.77)^a	.04
Friendship Scale	Speaking	0.58 (0.44 to 0.72)	<.001	0.49 (0.027 to 0.95)^a	.045
Physical activity
SF-36 PCS	Physical activity score^c	−0.32 (−1.27 to 0.63)	.44	0.71 (−0.60 to 2.02)^b	.14
	Stationary	1.67 (−2.06 to 5.4)	.32	−0.38 (−3.06 to 2.30)^a	.71
	Walking level	0.76 (−2.51 to 4.03)	.59	0.97 (−2.02 to 3.96)^a	.42
	Walking up	−2.31 (−4.48 to −0.13)	.04	1.68 (−7.00 to 10.36)^a	.62
	Walking down	0.73 (−2.36 to 3.81)	.59	−0.37 (−2.32 to 1.59)^a	.63
YPAS total hours	Physical activity score^c	0.57 (0.36 to 0.78)	.001	0.31 (−0.17 to 0.79)^b	.11
	Stationary	−1.57 (−2.68 to −0.47)	.01	−1.30 (−2.52 to −0.07)^a	.04
	Walking level	−1.18 (−2.46 to 0.091)	.06	−0.40 (−3.77 to 2.97)^a	.76
	Walking up	2.12 (1.06 to 3.18)	.003	5.06 (−0.31 to 10.43)^a	.06
	Walking down	1.85 (0.48 to 3.22)	.02	1.98 (0.80 to 3.16)^a	.01
YPAS kcal/week	Physical activity score^c	152.3 (97.8 to 206.8)	<.001	95.7 (50.0 to 141.4)^b	.01
	Stationary	−358.5 (−700.8 to −16.2)	.04	−230.5 (−551.9 to 90.9)^a	.12
	Walking level	−319.5 (−660.9 to 22.0)	.06	−51.3 (−791.3 to 688.7)^a	.86
	Walking up	567.9 (269.8 to 865.9)	.003	1,148.4 (263.9 to 2,032.9)^a	.02
	Walking down	431.9 (37.7 to 826.1)	.04	374.8 (31.3 to 718.3)^c	.04