Table 3.

Associations/Effects Between Sleep and Physical Activity Outcomes in Early Childhood

		Quality assessment
No. of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other	No. of participantsa	Overall effectb	Quality
8	Cross-sectional	Serious risk of biasc	Serious inconsistencyc	No serious indirectness	No serious imprecision	None	4,801	4 null, 2 positive, and 2 mixedd	Very low
0	Longitudinal	N/A	N/A	NA	N/A	N/A	N/A	N/A	Not assignable
0	Acute experimental	N/A	N/A	N/A	N/A	N/A	N/A	N/A	Not assignable
8	Chronic experimental	Serious risk of biase	No serious inconsistency	Serious indirectnesse	No serious imprecision	None	2,368	2 null, 3 positive, and 3 mixedf	Low

Note. PA outcome measures included sedentary time, LPA, MVPA, total accelerometry-derived activity counts, active outdoor play, or other indices of PA (e.g., meeting PA guidelines, outdoor time, participating in walking or biking, or extracurricular PA or sports participation). LPA = light physical activity; MVPA = moderate to vigorous physical activity; PA = physical activity; N/A = not applicable.

^aThe number of participants may not represent unique participants.

^bOverall effect key: Null = no statistically significant association/effect; positive = statistically significant association/effect in hypothesized direction; mixed = at least one statistically significant association/effect if more than one association/effect examined; negative = statistically significant association/effect in opposite of hypothesized direction.

^cDowngraded to low quality of evidence due to serious risk of bias (primarily from missing eligibility criteria and potential misclassification risk from measurement methods in some studies) and inconsistency of effect.

^dStudy effects were null (Dolinsky et al., 2011; Raza et al., 2019; Schmutz et al., 2017; Yu et al., 2011), positive (Hager et al., 2016; Hauck et al., 2018), and mixed (Hinkley et al., 2012; Kohyama, 2007).

^eDowngraded two levels from high to low due to serious risk of bias (i.e., lack of information regarding concealment and blinding and concerns for misclassification of the outcome due to self-report or parent report for sleep measures in some studies) and serious risk of indirectness (i.e., interventions varied considerably, and most had multicomponents so that the effects of sleep on PA could not be determined).

^fStudy effects were null (Haines et al., 2018; Taylor et al., 2018), positive (Alhassan et al., 2019; Taylor et al., 2017; Yoong et al., 2019), and mixed (Händel et al., 2017; Puder et al., 2011; Taylor et al., 2015).