Procedures
RECRUITMENT, RECRUITMENT, SECONDARY
Participants were recruited from across England from March 9, 2020 (both trials), to March 1, 2021 (NEON Trial), and March 26, 2021 (NEON-O Trial). Although most of the participants were recruited online, the trials used a mixed online and offline approach to participant recruitment. Recruitment was performed through paid online advertising on mental health websites (GBP £1900 [US $2360] spend) and printed magazines (GBP £2200 [US $2730] spend); promotional messaging distributed by mental health community groups (n=775) and primary health care practices (n=66); promotional messaging distributed on Facebook, Twitter, and Google (GBP £10,300 [US $ 12,790] spend to enhance the reach of messages); media appearances by the central study team; and the work of clinical research officers at 11 secondary care mental health trusts. Community groups were identified by the central study team, including through personal knowledge and searches of publicly available information. They were contacted by a study team administrator and offered approved promotional messaging to distribute. Clinical research officers approached potential participants in person and distributed promotional messaging through local authorized channels such as mailing lists of service users who had consented to be contacted about research studies. All promotional advertising and messaging conformed to principles approved in advance by the supervising research ethics committee [After recruitment, there was no planned human contact. All recruitment approaches directed potential participants to an online eligibility-checking interface that requested responses to a series of questions specified in the trial protocol [Eligible potential participants were provided with access to an online participant information sheet that included contact details for the study team in case clarification was needed. Participants completed an online informed consent form by providing an email address and optional telephone number. The consent process was concluded by clicking a link in an auto-generated email to validate the email address. After confirming consent, participants completed online forms to enable collection of baseline demographic information and completed all measures (MANSA, CORE-10, HHI, MHCS, Meaning in Life Questionnaire, and EQ-5D-5L). After form completion, participants were randomized using a web-based system validated by a clinical trials unit to intervention or control arms. All data considered in this paper are prerandomization data.