Funding for this research was provided by:
Michael Smith Foundation for Health Research (MSFHR 16606)
ZonMw (no. 91714344)
Human Frontier Science Program (LT001080/2017)
Received: 2 December 2017
Accepted: 18 June 2018
First Online: 4 July 2018
Ethics approval and consent to participate
: All participants provided written informed consent. The FARAO and Grey Power studies were approved by the medical ethical committee of the VU Medical Hospital; the Sint Franciscus Gasthuis study was considered outside the remit of the medical research involving human subjects act (Dutch WMO act) by the Sint Fransiscus Gasthuis medical ethical committee, which provided a written confirmation that the need for approval was waived.
: Not applicable.
: Between 06/2014 and 09/2015, KS was partially supported by a commercial grant of McRoberts BV (the Hague, the Netherlands). MN and RL are with McRoberts BV, the company that provided the physical activity classification algorithm. McRoberts BV benefits from publishing this paper as reference data for their customers. JD, MP, AM and AH do not report any competing interests.
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