Received: 30 September 2020
Accepted: 29 January 2021
First Online: 10 February 2021
Ethics approval and consent to participate
: All participants and/or their legal guardian provided written informed consent and local ethical committees from each contributing ICAD study approved individual study protocols. Prior to sharing data, data-sharing agreements were established between contributing studies and MRC Epidemiology Unit, University of Cambridge, UK.
: Not applicable.
: The authors declare that they have no competing interests.