Effectiveness evaluation of a remote accessibility assessment system for wheelchair users using virtualized reality

Objective: To determine the value of the Remote Accessibility Assessment System (RAAS), a 3-dimensional (3D) image reconstruction technology designed to analyze accessibility of the target built environment in a virtualized reality, in assessing a built environment's accessibility by calculating the congruence level between the RAAS and conventional in-person method. Design: Repeated-measures (within-subject) design. Setting: A university research laboratory. Participants: Three homes for people who use wheeled mobility devices. Intervention: Home physical environment was divided into several potential problem areas such as entrance, hallway, bathroom, and living room. Each area was identified by several tasks that might be performed in it. All possible tasks in each area within each home were evaluated using 2 methods: RAAS and the conventional in-person assessment. The evaluations were performed by a different home modification specialist for each method. Main Outcome Measures: Conventional in-person assessments Were cross-tabulated with assessments from RAAS, with which there are 4 possible assessment combinations. A true positive (checked-checked) occurs when the RAAS method checks the target task as problematic and it is also checked as problematic by the conventional in-person method. True negative (not checked-not checked), false positive (not checked-checked), and false negative (checked-not checked) were also identified as the same way. Results: The proportion of overall agreement was high at 94.1% and the overall sensitivity and specificity was 95.6% and 90.3%. respectively. A significant K coefficient of 857 and the 95% confidence interval of the odds ratio of 104.062 to 404.921 were calculated and a high level of overall agreement rate was shown. A high P value (.868) of the McNemar test implied that there was no marginal homogeneity, that is, no tendency to identify the task incorrectly in the positive or negative direction. Conclusions: This system proved that virtualized reality and 3D reconstruction technology may provide an effective means to investigate the architectural features of a built environment without an expert visiting the site. This system could become an efficient tool for the service provider and can provide expert service to underserved clients that would otherwise be unavailable.