1. International Journal of Cardiology
Is cardiac autonomic function associated with cardiorespiratory fitness and physical activity in children and adolescents? A systematic review of cross-sectional studies 
Ricardo Santos Oliveira, Alan Robert Barker, Kelly Michelle Wilkinson, Rebecca Anne Abbott, Craig Anthony Williams 
International Journal of Cardiology 
Volume 236, Pages (June 2017)
DOI: /j.ijcard
Copyright © 2017 Elsevier B.V. Terms and Conditions

2. Fig. 1
PRISMA flow diagram of the identification and selection procedures.
International Journal of Cardiology  , DOI: ( /j.ijcard )
Copyright © 2017 Elsevier B.V. Terms and Conditions

3. Fig. 2
Risk of bias of the individual studies. The maximal value of 24 reflects the lowest risk of bias. Studies are ranked according to the observed risk of bias.
International Journal of Cardiology  , DOI: ( /j.ijcard )
Copyright © 2017 Elsevier B.V. Terms and Conditions