Table 2.

VR-USOP.

1	Identify Barriers and Facilitators	•Use UTAUTM, STAM, MOLD-US or SCAIS models (Venkatesh et al., 2003; Phang et al., 2006; Chen and Shou, 2014; Wildenbos et al., 2018) •Clinical diagnosis and expert clinicians
2	Develop adequate VR and task	•Architecture design •Use older people technology design guidelines (Phiriyapokanon, 2011; Loureiro and Rodrigues, 2014) •Apply senior-UCD (Brox et al., 2017) •If training, use feedback guidelines (Morán et al., 2015) •Iterative prototyping
3	Define usability assessment	•Quantitative methods (e.g., SUS, TAM-based, UX-based questionnaires, PSSUQ) •Qualitative methods (e.g., post-experience interviews, think-aloud) •Additional methods (VR data, observation, psychophysiological measurements) •Assess usability and feasibility from medical professionals •If training, evaluate adherence •If immersive VR, evaluate cybersickness •If immersive VR with avatar, assess virtual embodiment •Consider PX for serious games and sense of presence for VR •Usability session should last 30 min approx.; more sessions can be included if there are experimental reasons
4	Test clinical use	•If usability results are unsatisfying, adjust VR system before clinical testing •If usability results are acceptable, start clinical efficacy testing

PSSUQ, post-study system usability questionnaire; PX, player eXperience; SCAIS, senior citizens' acceptance of information systems; STAM, senior technology acceptance model; SUS, system usability scale; UCD, user-centered design; UTAUTM, unified theory of acceptance and use of technology model; UX, user eXperience; VR, virtual reality.