The wearable landscape: Issues pertaining to the validation of the measurement of 24-h physical activity, sedentary, and sleep behavior assessment - Marco Giurgiu; Birte von Haaren-Mack; Janis Fiedler; Simon Woll; Alexander Burchartz; Simon Kolb; Sascha Ketelhut; Claudia Kubica; Carina Nigg; Irina Timm; Maximiliane Thron; Steffen Schmidt; et al. (Journal of Sport and Health Science)