Text and Data Mining valid from 2019-11-29
Received: 21 December 2018
Accepted: 12 November 2019
First Online: 29 November 2019
Ethics approval and consent to participate
: Ethical statement (reference number 2/2017) was obtained from the Ethics Committee of Human Sciences, University of Oulu, Finland. A written consent was obtained from all study participants.
: There are no identifiable details included.
: Hannu Kinnunen (HKi) and Heli Koskimäki (HKo) are employed by Oura Health, and Anna Maijala (AM) received a one month salary worth grant from Oura Health. As a company, Oura Health had no involvement in data analyses, interpretation or preparation of the article. All other authors of this paper declare no competing interests.