Triage nurses' clinical decision making: a multi-method study of practice, processes and influences

Abstract

Triage is a core decision making process used in hospital emergency departments to determine a person's need for medical assessment based upon the speed of intervention required to achieve an optimal clinical outcome. In many Western countries, nurse triage systems have evolved in response to evidence that established time to treatment as a strong predictor of emergency department mortality and morbidity. Notwithstanding a wealth of published evidence supporting the utility and reliability of standardised five-point triage scales throughout Australasia and Canada, researchers have emphasised the urgent need to optimise the consistency with which clinicians interpret and apply five-point triage scales in practice. Fundamental to improving triage consistency, is a clear description of both scope of practice and the environmental factor influencing decision making.

This thesis explores two features specific to emergency department triage in Australia; first, triage nurses' scope of practice, and second, the factors that influence the outcomes of their decision making in the real world. Using a unified model of psychological classification, the study program was interpreted using Cognitive Continuum Theory.

A sequential mixed method design that combined; survey data, observations of practice and a series of simulated decision tasks was undertaken in three phases. In Phase 1, triage nurses' scope of practice was explored, by describing the levels of experience, educational background and the training required for nurses to perform the triage role in Australia. Using a postal survey (N= 172), self-report data was collected to examine; performance frequencies, levels of autonomy and nurses' satisfaction with regard to a series of eighteen selected clinical decision tasks. Building on the results of nurses' self-reported decision behaviour, Phase 2 of the research program employed, a structured observational approach to study of twenty-six triage nurses performing 404 episodes of triage in one metropolitan emergency department. In the final phase of the research program, twelve controlled decision tasks were developed from Phase 2 data to study the decision behaviour of sixty-six nurses diagnosing urgency.

The key outcomes of interest resulting from this study were; a description of the education and training of Australian triage nurses, the development of a taxonomy of core decision types underpinning the triage role, and the identification of factors impacting the both the duration of the nurse-patient interaction at triage and nurses' levels of agreement using the ATS.

This thesis advances Hammonds's Cognitive Continuum Theory in two respects; first by describing nurses' diagnostic judgements in terms of both task conditions and task properties, and second by extending its application to the exploration of the situational influences impacting the outcomes of triage nurses' decision making in the real world. Future work is required to build educational programs and practice standards to improve triage consistency and that acknowledge the largely subjective nature of triage decisions in practice. In particular, efforts to maximise nurses' levels of agreement using triage scales must balance accountability requirements, with the need for timely, safe and consistent decision making.