2 Evidence gaps

This section describes the evidence gaps, why they need to be addressed and their relative importance for future committee decision making.

The committee will not be able to make a positive recommendation without the essential evidence gaps (see section 2.1) being addressed. The company can strengthen the evidence base by also addressing as many other evidence gaps (see section 2.2) as possible. This will help the committee to make a recommendation by ensuring it has a better understanding of the patient or healthcare system benefits of the technology.

2.1 Essential evidence for future committee decision making

Clinical benefits for severe agoraphobic avoidance in people with psychosis

Evidence on the clinical effectiveness of the technology at 6 months is essential for determining the technology's clinical and cost effectiveness. The committee has highlighted that a self-reported questionnaire such as the Oxford Agoraphobic Avoidance Scale (O‑AS) or the Agoraphobia Mobility Inventory (AMI) could be used to assess clinical change in agoraphobic symptoms. Data on any relapse or change in agoraphobic symptoms should be collected to assess if the benefits of treatment are sustained at 6 months.

Level of engagement and adherence

Evidence on engagement and adherence will support the NICE committee in assessing the real-world uptake of the technology and its acceptance by adults with severe agoraphobic avoidance with psychosis.

Healthcare resource use

Several costs are relevant to the overall resource impact of this technology and will be essential in understanding its resource impact and cost effectiveness. The costs include:

  • initial upfront costs, such as the licence and virtual reality (VR) headset costs

  • healthcare resource use during and after treatment, including healthcare professional grade and time needed to deliver treatment or support

  • costs associated with maintenance and lifespan of the hardware

  • the cost of extra sessions after the first 6 sessions (the initial full VR therapy intervention).

Adverse effects

Continued reporting of device (VR headset)-related and intervention (VR therapy)-related adverse events is essential to assess any risk involved in the continued use of the technology in the NHS.

2.2 Evidence that further supports committee decision making

Health-related quality of life

This outcome measures a person's perspective on how changes in their health state relate to their quality of life. The EQ‑5D is the preferred tool for measuring this outcome but non-standard measures such as the Recovering Quality of Life questionnaire may better capture benefits in people using mental health services within the NHS. This information can be included in health economic evaluations, for which quality of life is an important driver.

Generalisability

It is important to understand the characteristics of people using the technology to understand how the benefits from using the technology will be realised at the population level. This will ensure that appropriate guidance is given on the population group that would most benefit from this technology.