. 2018 Mar 16;5(1):e23. doi: 10.2196/mental.9519

Table 3.

The linear regression models without interaction components for the average of heart rate (HR), low frequency/high frequency (LF/HF) ratio, root mean square of the successive differences (RMSSD), recovery percentage, and recovery index during the first 3 hours of sleep. BMI: body mass index.

Outcome	HR	LF/HF ratio	RMSSD	Recovery percentage	Recovery index
Intercept, estimate (SE)	10.87 (0.66)^a	0.715 (0.115)^a	−15.32 (0.98)^a	−56.09 (3.25)^a	−28.27 (3.70)^a
Alcohol (g/kg), estimate (SE)	8.49 (0.29)^a	0.425 (0.051)^a	−12.24 (0.44)^a	−33.67 (1.45)^a	−36.63 (1.65)^a
Physical activity class, estimate (SE)	−0.48 (0.06)^a	−0.019 (0.011)	0.37 (0.09)^a	1.62 (0.31)^a	1.81 (0.35)^a
Age (0=18 years), estimate (SE)	−0.03 (0.01)^b	−0.001 (0.002)^a	0.14 (0.02)^a	−0.06 (0.05)	−0.08 (0.06)
BMI (0=18.5 kg/m²), estimate (SE)	0.22 (0.03)^a	0.002 (0.005)	−0.26 (0.04)^a	−0.81 (0.14)^a	−0.89 (0.15)^a
Gender (0=female, 1=male), estimate (SE)	−1.70 (0.21)^a	0.014 (0.037)	2.09 (0.32)^a	7.22 (1.06)^a	5.24 (1.21)^a
Baseline sleep HR (0=38 bpm), estimate (SE)	−0.33 (0.01)^a	−0.021 (0.002)^a	0.41 (0.02)^a	1.67 (0.06)^a	0.86 (0.07)^a
Adjusted coefficient of determination for the model	0.267	0.039	0.245	0.230	0.135

^aP<.001.

^bP<.01.