Table 1

Study designs

	Study design
Authors	Cross-sectional	Longitudinal	Experimental randomised study
Chaput et al 2011³⁶			X
Desai et al 2010²⁵	X
DiFrancisco-Donoghue et al 2019²⁶	X
Exelmans et al 2015²⁷	X
Hellström et al 2015²⁸	X
Scharrer et al 2014³⁵		X*
Mario et al 2014²⁹	X
Rudolf et al, 2020³³	X
Smyth et al 2007³⁴		X
Wallenius et al 2009³²	X
Weaver et al 2009³⁰	X
Zapata et al 2006³¹	X

*Scharrer et al was designed like a randomised experimental study but there were no baseline assessments of outcomes. Therefore, it was considered a prospective cohort study.