Table 2

Participants and locations

	Age
Authors	Adolescents (10–24 years old)	Adults (25+ years old)	Boy/girl ratio	Location	N total
Chaput et al 2011³⁶	15–19		All boys	Denmark	22
Desai et al 2010²⁵	14–18		1845/2139	USA	3984
DiFrancisco-Donoghue et al 2019²⁶	18–22		N/A	USA & Canada	65
Exelmans et al 2015²⁷	18	94	370/474	Belgium	844
Hellström et al 2015²⁸	13–18		3872/3885	Sweden	7757
Scharrer et al 2014³⁵	13–15		105/69	Mid-Atlantic states, USA	176
Mario et al 2014²⁹	18	27	All boys	United Kingdom	45
Rudolf et al 2020³³	20	30	980/86	Germany	1066
Smyth et al 2007³⁴	18–20		73/27	New York, USA	100
Wallenius et al 2009³²	12–18		2500/1585	Finland	4085
Weaver et al 2009³⁰	19	90	271/291	Seattle, USA	562
Zapata et al 2006³¹	14		376/415	São Paulo, Brazil	791