Funding for this research was provided by:
Discovery Vitality (N/A)
Received: 1 October 2018
Accepted: 2 May 2019
First Online: 31 May 2019
Ethics approval and consent to participate
: Before any contact with participants we obtained protocol approval from the University of Witwatersrand Ethics Committee and were granted an exemption from the University of Pennsylvania Institutional Review Board. Given the pre-existing language in the Vitality membership agreement regarding use of data for research purposes, including collaboration with outside research groups, we were granted a waiver of informed consent by the University of Witwatersrand Ethics Committee.
: Not applicable.
: AG, RL and JZ have no financial disclosures to report. AMB is a member of the editorial board of this journal. PAS, KGV, and AMB have received research funding from the Vitality Institute. JP and DP are/were employees of Discovery Vitality. Given this relationship, JP and DP were not involved in data analysis but provided only operational support and expertise. KGV is a principal at the behavioral economics consulting firm VAL Health and has received consulting income from CVS Caremark and research funding from Humana, CVS Caremark, Discovery (South Africa), Hawaii Medical Services Association, and Oscar, none of which are related to the work described in this manuscript.
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