Patricia L. Haynes, PhD, Health Promotion Sciences, Mel & Enid Zuckerman College of Public Health, University of Arizona; Elizabeth Hillier, BS, Health Promotion Sciences, Mel & Enid Zuckerman College of Public Health, University of Arizona, Dept. of Physiology, College of Medicine, University of Arizona; Cody Welty, BS, Health Promotion Sciences, Mel & Enid Zuckerman College of Public Health, University of Arizona

Purpose/Objectives
The purpose of this project is to examine whether 911 telecommunicators who take more dispatched calls have more intense negative emotions from pre to post-shift, as compared to 911 telecommunicators who take fewer dispatched calls.

Background
The 911 emergency response system is a vital public health safety net that handles approximately 240 million calls per year. 911 telecommunicators are essential first responders within this system, frequently tasked with time-sensitive choices about how to solve complex problems while managing the strict requirements of workplace presence. Despite the known stressful characteristics of this occupation, few studies have examined objective 911 job demands and the impact of these demands on mental health outcomes in this at-risk group.

Methods
The study employed a prospective, intensive longitudinal design examining call volume and pre and post-shift ratings of negative emotions across the course of one week (M = 6.63 days, SD = 2.29 days). Participants were 48 emergency telecommunicators employed at an agency in Arizona. Call frequency was gathered through the agency Computer-Assisted Dispatch (CAD) database. Pre- to post-shift change in negative emotions was measured by the Visual Analogue Scale, a self-report, valid and reliable measure developed for the daily assessment of various emotions (irritated, stressed, worried, and fatigued). Mixed linear modeling was employed examining both between- and within-person levels of analysis.

Findings
On days when subjects had more-than-usual number of dispatched calls per hour, they subsequently reported higher levels of post-shift irritability (B = 2.06; SE = .95, p < 05, 95% CI [.19, 3.93]). Higher levels of pre-shift irritability (B = .25, SE = .07, p < .001, 95% CI[.11, .39]) and longer working hours (B = 1.50, SE = .59, p < .05, 95% CI[.33, 2.67]) also predicted higher levels of post-shift irritability. The between-person effect of call volume was not significant, indicating that people with a greater number of calls did not have higher levels of post-shift irritability. Additionally, no within or between subject effects for call volume were observed for stressed, worried, or fatigued; the best predictor of post-shift negative emotion across all variables was the same pre-shift negative emotion. Analyses controlled for demographics and night-shift work.

Discussion
911 telecommunicators have an individual set-point in terms of call volume. Irritability may be a signal that this set-point has been exceeded. In addition to call volume, shift length and pre-shift emotional state are potential mechanisms for negative post-shift emotions. Strengths of this study include a prospective design and an objective measure of call volume.

Conclusions
In summary, a higher-than-usual daily 911 call volume was associated with more intense post-shift irritability, when controlling for pre-shift irritability and shift length. Future research is warranted that examines the impact of shift-related changes in negative and positive emotions across longer timescales, as well as the impact of irritability and other negative emotions on patient/caller care.

Tags: Empirical study, Job and Task Design, Organization- and Job-Level Environments and Practices, Psychological and Biological Effects of Job Stress, Public safety, Workplace Stress; Outcomes; and Recovery