Clinical and Cost Effectiveness of Alpha-Stim AID CES

Participants will have a baseline visit (day 1, visit 1) following identification as potentially eligible. The baseline visit will be face-to-face with a member of the research team, held at routine facilities used by the IAPT service. At the baseline visit, the participant will be consented for participation, have a urine pregnancy test first (if a female of child bearing potential) and the research team will administer the GAD-7 secondly, followed by EQ-5D-5L, WASA, PHQ-9, Athens, and CSRI surveys. Participants will then be instructed on how to use the Alpha-Stim AID device, and will have their first 60 minute, self-directed treatment session at home. All further visits will be facilitated via telephone, scheduled between the research team and participant, within a 5 calendar day window of each time point. At visit 2 (week 4), visit 3 (week 6), visit 4 (week 8), visit 5 (week 12) and visit 6 (week 24), the research team will administer the GAD-7, EQ-5D-5L, WASA, PHQ-9 and Athens. The CSRI will be repeated only at visit 5 and 6. Compliance with the 60 minute daily treatment session will also be assessed during the 6 or 12 week treatment window, in addition to any adverse events. The 60-minute self-directed Alpha-Stim AID treatment sessions are undertaken at participant's home, on a daily basis for 6 weeks for all participants. During this 6-week period, participants will be on the waiting list for high intensity psychological therapy interventions. Following 6 weeks of Alpha-Stim AID CES treatment, participants have the option to receive a further 6 weeks of treatment, which is likely to coincide with start of high intensity psychological therapy interventions as clinically indicated. Following a maximum of 12 weeks' treatment with Alpha-Stim AID CES, all participants will cease to receive treatment on study. All participants will continue to receive standard care assessment, as undertaken by the NHS IAPT service, standard care high intensity psychological therapy interventions as clinically indicated and provided by the NHS IAPT service, and standard care pharmacological treatments as prescribed by the participant's GP. Participation in this study will not influence nor compromise standard care treatment - all study procedures are additional to standard care. Participation in the study will have no impact upon the duration of the waiting time for high intensity psychological therapy interventions.