. 2021 Oct 14;23(10):e18403. doi: 10.2196/18403

Table 4.

Linear regression analysis of Peabody Developmental Motor Scales-Second Edition standard scores by season and Fast Fourier Transform signals at 12 months: stationary and locomotion subtests and gross motor and fine motor as the outcome, respectively.

Category and variable^a			Estimate (SE)		t test (df)		P value
Stationary
	(intercept)	9.23 (0.19)		47.9 (99)		<.001
	one-third day	0.04 (0.02)		2.17 (99)		.03^b
Locomotion
	(intercept)	7.16 (0.43)		16.48 (97)		<.001
	summer	0.71 (0.75)		0.94 (97)		.35
	one-third day	0.19 (0.04)		4.61 (97)		<.001^b
	summer: one-third day	–0.13 (0.07)		–1.93 (97)		.06^c
Gross motor
	(intercept)	26.41 (0.63)		42.03 (97)		<.001
	summer	0.57 (1.09)		0.52 (97)		.60
	one-third day	0.24 (0.06)		3.97 (97)		<.001^b
	summer: one-third day	–0.17 (0.10)		–1.73 (97)		.09^c
Fine motor
	(intercept)	21.08 (0.5)		42.15 (97)		<.001
	summer	0.34 (0.86)		0.39 (97)		.70
	one-third day	0.11 (0.05)		2.36 (97)		.02^b
	summer: one-third day	–0.15 (0.08)		–1.89 (97)		.06^c

^aThe Fast Fourier Transform signals were multiplied by 10,000 in regression models so that the estimated effect sizes were for every 10,000-unit increase in the Fast Fourier Transform signals.

^bStatistical significance level at α=.05.

^cStatistical significance level at α=.10.