Efficacy and Mechanisms of Virtual Reality Treatment of Phantom Leg Pain.Home-Based Treatment

the change in phantom limb pain score pre and post each VR intervention, at baseline, after the VR intervention and in the follow-up sessions as assessed using an 11-point numerical rating pain scale (0 - minimum score/no pain; 10 maximum score/pain as bad as you can imagine) assessing the current PLP level.

The change in the phantom limb pain quality between baseline, post-intervention, and follow-up sessions using McGill Short Form Questionnaire that measures the characteristics of pain (e.g., throbbing, etc.) using a 4-point rating pain scale (0 - minimum score - none: better outcome /4 maximum score - severe: worse outcome).

average pain intensity since the previous intervention on an 11-point numerical rating pain scale; (0 - minimum score/no pain; 10 maximum score/pain as bad as participants can imagine); higher scores indicate higher level of pain (worse outcome)

The Frenchay Activities Index (FAI): a scale measuring the physical function and daily activity that has excellent reliability in subjects with lower-limb amputation in predicting quality of life. 0 minimum score - 45 maximum score; higher scores indicate more daily activities (better outcome).

The 12-Item Short Form Health Survey (SF-12): a brief measure of quality of life and functional capacity that has been validated in patients with amputation and PLP. 0 minimum score - 100 maximum score. Higher scores indicate lower physical and mental health (worse outcome).

The Pain Interference Scale from the Brief Pain Inventory (BPI): this assesses the degree to which pain interferes with daily activities using a 0-10 numeric rating scale. 0 minimum score - 10 maximum score. Higher scores indicate higher pain interference (worse outcome).

The Hospital Anxiety and Depression Scale (HADS): the HADS is a 14- item measure assessing both depressive and anxiety symptoms. In addition to providing separate scores for anxiety and depression, the HADS also provides a measure of global negative affect. 0 minimum score - 42 maximum score. Higher scores indicate more depression and anxiety (worse outcome)

The 13-item Pain Catastrophizing Scale: this scale investigates pain catastrophizing, which has been highly associated with pain severity and disability after amputation. 0 minimum score -52; Higher scores indicate higher tendency to catastrophizing (worse outcome)

Insomnia Severity Index: this is a 7-point scale that measure insomnia, a symptom associated with PLP. 0 minimum score - 28 maximum score; higher scores indicate more insomnia (worse outcome)

Technology Acceptance Scale (Morris et al., 1997): this is a 7-point scale that measure level of acceptance of the VR system. 0 minimum score - 133 maximum score; higher scores indicate low level of acceptance (worse score)

System Usability Scale (SUS): Scale measuring the usability of each game; minimum score 10 - maximum score 50. Higher scores indicate less usability (worse outcome).

Simulator Sickness Questionnaire, which test for the presence of symptoms of cybersickness (e.g., general discomfort) on a 4-point numerical rating scale (0 - minimum score/no symptom; 4 maximum score/severe symptom)

Brief Slater-Usoh-Steed Presence Questionnaire. 7 minimum score - 42 maximum score. Higher scores indicate more presence in the VR (better outcome)

The Modified Limb Deficiency and Phantom Limb Questionnaire: this questionnaire assesses the usage of prosthesis (yes/no) and non-painful phantom limb experiences (presence/absence), including perceived position (e.g., presence/absence of telescoping) and ability to move the phantom (yes/no).

visual analogue scale that evaluates treatment satisfaction; 0 minimum score - 10 maximum score; Higher scores indicate more treatment satisfaction (better outcome)