Data obtained in this study will be analysed to examine the relationships between nursing tasks, self-reported and physiological measures of stress and to assess the effect of occupational stress on multiple work outcomes. The results will inform theoretical understanding of nurse stress and its determinants and suggest possible targets for intervention to reduce stress and associated harmful consequences.

BackgroundStress in health care professionals may reflect both the work and appraisal of work and impacts on the individuals, their patients, colleagues and managers.PurposeThe purpose of the present study is to examine physiological and psychological effects of stressors (tasks) and theory-based perceptions of work stressors within and between nurses in real time.MethodsDuring two work shifts, 100 nurses rated experienced stress, affect, fatigue, theory-based measures of work stress and nursing tasks on electronic diaries every 90 min, whereas heart rate and activity were measured continuously.ResultsHeart rate was associated with both demand and effort. Experienced stress was related to demand, control, effort and reward. Effort and reward interacted as predicted (but only within people). Results were unchanged when allowance was made for work tasks.ConclusionsReal-time appraisals were more important than actual tasks in predicting both psychological and physiological correlates of stress. At times when effort was high, perceived reward reduced stress.Electronic supplementary materialThe online version of this article (doi:10.1007/s12160-015-9746-8) contains supplementary material, which is available to authorized users.

Findings provide little support for a resource depletion model; however, the finding that control and reward both predicted fatigue is consistent with a motivational account of fatigue.

Nurse managers should review the level of interruptions to nurses' work and ensure appropriate levels of supervision.

Finding good discriminant content validity for demand and reward measures means these measures are usable and our quantitative results can guide item selection. By contrast, effort and control measures had limitations (in relevance and representativeness) presenting a challenge to the implementation of the theories. Statement of contribution What is already known on this subject? While the reliability and construct validity of Demand-Control and Effort-Reward-Imbalance (DC and ERI) work stress measures are routinely reported, there has not been adequate investigation of their content validity. This paper investigates their content validity in terms of both relevance and representativeness and provides a model for the investigation of content validity of measures in health psychology more generally. What does this study add? A new application of an existing method, discriminant content validity, and a new method of assessing instrument representativeness. 'Pure' DC and ERI items are identified, as are constructs that are not fully represented by their assessment instruments. The findings are important for studies attempting to distinguish between the main DC and ERI work stress constructs. The quantitative results can be used to guide item selection for future studies.