Assessing the impact of stressors on performance: observations on levels of analyses.

Applied researchers often are required to rely on limited laboratory studies to estimate the effects of various stressors on actual job performance. It can be difficult to select measures which lend themselves to implementation in laboratory settings while also providing sufficient capability to predict complex 'real-world' performance. Studies which employ simulations of operationally-relevant tasks and those which include the administration of basic cognitive tests are favored by many applications-oriented researchers. This is despite the fact that such a testing approach may limit sensitivity due to the requirements for extensive practice on these tasks in order to obtain stable results. Studies which use physiological assessments appear to be less readily accepted by applied researchers because of the difficulties in drawing a direct link between physiological indexes and operational performance. However, there are arguments to be made for the inclusion of physiological evaluations with the more traditional, performance-based measures. Data from three studies are cited here to support the value of using a multifaceted approach to the study of operationally-relevant stressors. Although these studies were not conducted to systematically investigate the relative merits of performance, cognitive, and physiological assessments, they do serve to highlight the fact that inclusion of all three types of tests tend to maximize the validity, interpretability, and sensitivity of applied research.