Developing multiple shortened forms of virtual reality-based color trails test

The Color Trails Test (CTT) is a pencil-and-paper (P&P) neuropsychological test. The CTT is divided into two parts that assess sustained visual attention (Trails A) and divided attention (Trails B). The CTT can also be performed in a virtual reality setting (VR-CTT) introducing a wider spatial range of targets. In cases of multiple assessments, repeating the same CTT configuration can bias the results due to fatigue and learning effects. The aim of this study is to create five different short versions of the VR-CTT. The different forms were created by rotating or flipping the original targets spatial layout on one of the axes and by ending it at ball #13. Healthy young participants (N = 15) performed the shortened VR-CTT forms (in a counterbalanced order), the P&P CTT and the original VR-CTT. We found no difference between the completion times of the five forms (p > 0.2), and a significant difference between Trails A and B across all forms (p < 0.04). Additionally, there was no evidence of a learning effect between trials (p > 0.4). Moreover, the shortened VR-CTT forms showed correlations with the P&P CTT (p < 0.05) and with the original VR-CTT (p < 0.06). These findings suggest that all five forms have an equal level of difficulty and that the different forms managed to mitigate the learning effects reported for repeated testing of the same spatial layout. This opens the possibility of applying the shortened VR-CTT forms for research settings and sets the basis for developing it into a clinical diagnostics tool.