3.1 NICE did a rapid review of the published literature on the efficacy and safety of this procedure. This comprised a comprehensive literature search and detailed review of the evidence from 10 sources, which was discussed by the committee. The evidence included 3 systematic reviews and/or meta-analyses, 2 randomised controlled trials (1 of which resulted in 2 publications), 2 non-randomised comparative studies, 2 case series and 1 single case report. It is presented in table 2 of the interventional procedures overview. Other relevant literature is in the appendix of the overview.
3.2 The professional experts and the committee considered the key efficacy outcomes to be: depressive symptoms, quality of life, and reduction in other treatments and hospital admissions.
3.3 The professional experts and the committee considered the key safety outcomes to be: device failure, infection, and worsening of mood symptoms including risk of suicidality.
3.5 The committee noted that there is a high incidence of side effects associated with the procedure including voice change, cough and dyspnoea. The side effects generally decrease over time and the treatment is generally well tolerated.
3.6 The committee was informed that there may be a better response to this intervention if the patient's symptoms have responded to electroconvulsive therapy.
3.7 The committee noted that, in common with other therapies for depression, studies on this procedure show a placebo effect.
3.8 The committee was informed that, if needed, the patient can temporarily deactivate the device before requesting removal by a clinician.