Funding for this research was provided by:
Suzhou Municipal Science and Technology Bureau (ss2019069)
Received: 20 August 2019
Accepted: 16 March 2020
First Online: 30 March 2020
Ethics approval and consent to participate
: The study design was approved by the ethical review committee of Peking University. All participants gave written informed consent.
: Not applicable.
: Dr. Chenkai Wu provides paid consultative services to Health Keepers, a health data analytics start-up in China.