Desirable Deviations In Medical Decision Making In The Pre-Hospital Setting: A Fuzzy-Trace Theory Approach
Introduction: Decision-making is a critical aspect of emergency medical treatment in the prehospital setting, from patient triage during a mass casualty incident to determining when an advanced directive should be executed. Use of protocols has become the standard for ensuring that the best possible care is provided to patients by emergency medical services (EMS). Studies on EMS protocols - including those by Frazier and Cannon (1974) on underdiagnosed myocardial infarction, Pozen (1977) on Electrocardiogram (EKG) transmissions to Emergency Departments, and Ruppert (1999) on the determination of breathlessness of a simulated patient - have shown that protocols improve patient outcomes. However, none of these studies has examined how pre-hospital providers make medical decisions and what information they use. The purpose of this current study is to determine the relative importance of gist (qualitative) versus verbatim (quantitative) representations in EMS decision-making. Prior researchers have assumed that accurate verbatim representations of protocols would have a greater contribution to how decisions are made. However, recent studies of the hospital setting showed that reliance on gist representations increases with expertise (Reyna & Lloyd, 2006). Although these settings are not identical, they share similarities that would suggest that reliance on gist representations would also increase in EMS providers with higher levels of experience. Thus, we hypothesize that use of gist (as opposed to verbatim) representations would be highest among the most experienced providers. Method: The study was administered to 217 pre-hospital care providers (68.7% male) via an anonymous online survey. First, participants were given seven medical case scenarios in which they had to evaluate a patient's clinical presentation and answer questions about how they would treat that patient, followed by questions regarding how the decision was made, and their confidence in that decision. Participants then self-reported their use of gist and verbatim representations when providing treatment in real situations to patients both in general and in one of six categories (Minor Trauma, Major Trauma, Cardiac, Respiratory, Allergic Reaction and Unresponsive); a relative gist index was calculated from these responses. Third, participants were asked to correctly recognize the presented symptoms from the medical case scenarios from lists that included gist-consistent distractors. Finally, participants provided their EMS background/experience, demographic information, and completed the Cognitive Reflection Test (CRT; Frederick 2005). Results: In a medical case study with a desirable deviation from protocol, those who chose the gist-based response had a higher average certification level than those who chose the verbatimbased response. Consistent results were found with a similar case study, in that those who chose the desirably deviating treatment had a higher relative gist index score than those who chose the protocol-based answer. Additionally, there was a negative correlation between the verbatim questions and the level of experience, showing that as experience increased, use of verbatim traces decreased. Last, the CRT score negatively correlated with provider's experience level. Discussion: Results support the hypothesis that use of gist representations increases with both experience and expertise level in the pre-hospital setting, consistent with fuzzy-trace theory. Given the nature of EMS training, which is mostly composed of brief classroom and practical sessions undertaken by many individuals with little to no medical experience, it is not surprising that, initially, there may be limited gist representations to draw from, resulting in reliance on verbatim representations. Over time, one would expect this to shift based on how cognitively active the EMS provider is. Currently, EMS re-training and evaluation are almost entirely verbatim-based which provide an assessment inconsistent with how experienced providers operate in the field, namely, by using gist. Opportunities for improving EMS training and continuing education are discussed.
Medical Decision-Making; Emergency Medical Services; Fuzzy-Trace Theory
M.A., Developmental Psychology
Master of Arts
dissertation or thesis