Performance prediction and limiting resource identification with nonlinear causal resource analysis

Nonlinear Causal Resource Analysis (NCRA) is a relatively new method for task analysis and prediction of human performance based on the resource economic performance modeling constructs of General Systems Performance Theory (GSPT). NCRA was investigated in 30 subjects executing three mobility related tasks (gait, stair climbing, and obstacle course negotiation). A high degree of agreement (r=0.92, 0.95, and 0.96) was found with expert raters who used a visual analog scale to estimate performance of 30 subjects executing these tasks. As part of the NCRA prediction methodology, limiting performance resources are also identified (i.e., performance resources associated with lower level subsystems that limit execution of the higher level task to a specific level of performance). There is no other systematic method known for accomplishing this useful clinical objective; the limiting resources represent targets of therapy for pathologic subjects. Results add to the body of support for NCRA as an alternative to regression analysis for prediction as well as a tool for task analysis and also suggest utility for therapy planning.