Tracey Barron

Academic Research

By Tracey Barron

Humans are designed to work during the day and recuperate at night. So it comes as no surprise that a decline in performance has been documented in people working 12-hour shifts.1 An Emergency Medical Dispatcher’s (EMD) performance can be affected as much by tiredness and sleep disturbance as any other shift worker; mistakes, errors, and omissions are made when the mind and body cannot function at their best.

While it has been noted that some workers actually enjoy the variety of rotating shifts and that shiftwork can provide advantages to society at large,2 the single, prominent conclusion from earlier studies is that additional research is needed in order to eliminate the harmful aspects of shiftwork.

In her book Asleep in the Fast Lane: The Impact of Sleep on Work, Lydia Dotto captured the dilemma faced by all 24-hour dispatch systems: “Industrialized societies are the ones most divorced from the natural, primitive cycle of day and night and they are also the most dependent on and vulnerable to complex technologies whose failure (often brought about by human error) can exact a huge social and economic toll.”3

And that’s where the International Academies of Emergency Dispatch (IAED) helps pick up the slack these many years later. Let’s first review the factors.

Effects of shiftwork on EMDs

Factors affecting performance are common among occupations, and they include:

•Physical factors such as health and age

•Psychological factors such as attitude toward work, motivation, sleep deprivation, and stress

•Nature of work to be performed (the type: physical or mental, complexity: decision-making or rote work, and schedule: day work or shiftwork)

While human performance often depends on the individual’s internal clock—night owls versus morning doves, for example—in some occupations, the shift system and its unconventional clock cannot be avoided. Due to scheduling demands, it’s not always the early bird that gets the day shift or the night owl that works the hours before dawn. This, of course, includes emergency dispatch.

Shiftwork and its effect on EMDs

A recent study looking at productivity and performance of the EMD signified an opening into research regarding the impact shiftwork could have on dispatch compliance. Specifically, the London Ambulance Service (LAS) NHS Trust studied whether the shift an EMD works has any bearing on the ability to rapidly categorize calls and subsequently facilitate the dispatching of appropriate emergency ambulance personnel.4

LAS uses the Medical Priority Dispatch System (MPDS) to triage emergency 9-9-9 calls, and more than 90,000 calls a month (about one-fifth of the total number of calls received in the U.K.) are handled at LAS headquarters.

Strict compliance to the protocol through a quality management program is an integral component in LAS’ evaluation of EMD performance, and feedback plus patient outcomes are central to the study’s findings.


For the study, a database consisting of 1,373 9-9-9 calls coming into LAS during a consecutive three-month sampling of emergency calls (June-August 2006) were randomly reviewed for compliance to the MPDS Protocol.

Day shift was defined as the hours between 7 a.m. and 7 p.m., and night shift applied to the hours between 7 p.m. and 7 a.m. LAS staff work through a 24/7 rotating shift pattern. Although those on the day shift handle more cases than night shift EMDs, the data was analyzed for mean compliance, which showed no statistical difference when adjusted for shiftwork.


The results of this study show that the use of a structured set of symptom- and incident-based protocols for triaging emergency 9-9-9 calls leads to equally high levels of compliance irrespective of the shift being worked, whether day or night.

In addition, the findings suggest that a protocol-driven process helps alleviate some of the many factors that contribute to mistakes, errors, and omissions being made, especially across periods of time in which the mind and body may not function at their best.

According to the study’s authors, this is an important conclusion in the world of the ambulance service where time can be crucial to a patient’s outcome, and where the accurate triage of a patient can directly impact the speed and level of response and care.


1 Rosa RR. Performance, alertness, and sleep after 3.5 years of 12 h shifts: a follow up study. Work &. Stress 1991; 5: 107-116.

2 Peter Finn, “The effects of shift work on the lives of employees,” Monthly Labor Review, October 1981, pp. 31-34; (accessed Sept. 23, 2013).

3 Dotto L. Asleep in the fast lane: the impact of sleep on work. Toronto (Canada); Stoddard Publishing Co. Ltd.; 1990.

4 John Afolayan, et al., Consistency of Emergency Medical Dispatchers’ Decisions Using a Protocol-Based Triage System, Annals of Emergency Dispatch & Response, Vol. 1, Issue 2, pp. 18-22.