Table 1.

Association between sleep duration and adiposity in children aged 0–4 years

No of studies	Design	Quality Assessment					No of participants	Absolute effect	Quality
		Risk of bias	Inconsistency	Indirectness	Imprecision	Other
Mean age ranged between 0 and 4.9 years. Data were collected cross-sectionally and up to 9.5 years of follow-up. Sleep duration was assessed by actigraphy or parent report. Adiposity was assessed objectively as body weight, body mass index (absolute, z-score or percentile), waist-for-length ratio, weight status (different definitions for underweight, normal weight, overweight, obese) or % body fat/fat mass/fat mass index (bioelectrical impedance, dual-energy X-ray absorptiometry, skinfolds).
13	Longitudinal studya	No serious risk of bias	No serious inconsistency	No serious indirectness	No serious imprecision	None	31,482	Out of 13 longitudinal analyses, 10 reported a significant association between shorter sleep duration and adiposity gain [17–26], 2 reported null findings [27, 28], and 1 reported that longer sleep duration predicted adiposity gain [29].	LOW
18	Cross-sectional studyb	No serious risk of bias	No serious inconsistency	No serious indirectness	No serious imprecision	None	30,829	Out of 18 cross-sectional analyses, 10 reported a significant association between shorter sleep duration and adiposity [23, 26, 30–37], 7 reported null findings [24, 25, 27, 28, 38–40], and 1 reported that sleep duration was positively associated with BMI z-scores [41].	LOW

Due to heterogeneity in the measurement of sleep and adiposity, a meta-analysis was not possible

^aIncludes 13 longitudinal studies [17–29]

^bIncludes 18 cross-sectional studies [23–28, 30–41]