Measuring equipment used in the Netherlands (<b>Figure 1A</b>) and in Malawi (<b>Figure 1B</b>).

<p>Abbreviations used in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0057209#pone-0057209-g001" target="_blank">Figure 1B:</a> A = board for placement of the feet, B = board for placement of the camera,1 = longitudinal line, 2 = mediolateral line</p

Static foot geometry.

<p><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0057209#pone-0057209-g002" target="_blank">Figure 2A:</a> Medial Angle. Angle between the center of the medial malleolus, the navicular tuberculum and the medial center of the first distal metatarsal head. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0057209#pone-0057209-g002" target="_blank">Figure 2B:</a> Navicular height/foot length ratio.</p

Mean plantar pressure.

<p>Left panel: The MP distribution for the Malawian group; middle panel: The MP distribution for the Dutch group; Right panel: The difference in MP between the Malawian and Dutch group. The coloured squares indicate that the MP is statistically different (p<0.007) between the groups and the black small lines indicate that the groups were not significantly different. Note that for both groups only pixels are shown with a mean output above 0.5N</p

Trajectory of the Center of Pressure.

<p>Upper left panel: the MP distribution for the Dutch group including the CoP path of the Dutch and Malawian group. Upper right panel: Difference in relative vCoP: Malawi group minus Dutch. Lower panels: the difference in CoP path for the mediolateral (left panel) and anteroposterior (right panel) direction. The red bars indicate that the CoP path/vCoP differs significantly between both groups.</p

The concurrent validity and reliability of virtual reality to measure shoulder flexion and scaption range of motion

Background Shoulder pain commonly has a detrimental impact on patient’s work and social activities. Although pain is the most common reason for seeking care, a reduction in shoulder range of motion (ROM) is another common impairment. ROM assessment is used as an evaluation tool and multiple methods are available to measure shoulder ROM. Virtual reality (VR) has been introduced into shoulder rehabilitation, mostly when exercise and ROM measurement is indicated. This study evaluated the concurrent validity and system reliability of active ROM measurements of VR for people with and without shoulder pain.Methods Forty volunteers participated in this study. Virtual goniometry was used to assess active shoulder ROM. Participants performed flexion and scaption to six predetermined angles. Measurements from the VR goniometer and smartphone inclinometers were recorded simultaneously. To assess reliability, two identical test sequences were performed.Results The concurrent validity ICCs were 0.93 for shoulder flexion and 0.94 for shoulder scaption. The VR goniometer application on average systematically overestimated the ROM compared to the smartphone inclinometer. The mean difference between goniometer values was −11.3 degrees for flexion and −10.9 for scaption. The system reliability was excellent with an overall ICC of 0.99 for the flexion movements and 0.99 for the scaption movements.Conclusion Although the VR system demonstrated excellent reliability, and high ICC’s for concurrent validity, the large range between the lower and upper 95% CI limits suggests it lacks measurement precision. This suggests VR, as used in this study, should not be used interchangeably with other measurement tools.</p