Funding for this research was provided by:
Programme Grants for Applied Research (RP-PG-1210-12011)
Received: 29 September 2020
Accepted: 1 February 2021
First Online: 17 February 2021
Ethics approval and consent to participate
: Approval received from East of England – Essex Research Ethics Committee (reference number 13/EE/0249); National Offender Management Service NRC (reference number 2013–187).
: Not applicable.
: The authors declare that they have no competing interests.