Kathleen A. Harder

Weighting Waiting: Evaluating the Perception of In-Vehicle Travel Time Under Moving and Stopped Conditions

Experiments are described in which traditional computer-administered stated-preference (SP) data are compared with virtual experience SP data to ascertain how people value stopped delay compared with stop-and-go or free-flow traffic. The virtual experience SP experiments were conducted by using a wraparound driving simulator. The two methods produced different results: the traditional computer-assisted SP data suggested that ramp delay is 1.6 to 1.7 times more onerous than delay on freeways, whereas the virtual experience SP data based on the driving simulator suggested that freeway delay is more onerous than ramp delay. Several factors are advanced to explain the differences, including recency, simultaneous versus sequential comparison, awareness of public opinion, intensity of the stop-and-go traffic, and the goal-directed nature of driving in the real world. However, without further research, it is unclear which, if any, of these factors will eventually prove to be the right one. What is clear is that a comparison of the computer-administered SP data with virtual experience SP data produces different results, even though both procedures strive to find the same answers in nominally identical sets of conditions. Because people experience the world subjectively and make decisions on the basis of those subjective experiences, future research should be aimed at better understanding the differences between these subjective methodologies.

Second Consensus Development Conference on the Safety of Intravenous Drug Delivery Systems—2008

In 1999, the first Consensus Development Conference on the Safety of Intravenous Drug Delivery Systems was held to evaluate the relative safety and cost of available nonelectronic i.v. drug delivery systems for parenteral medications. Included in the evaluation were the use of manufacturer-prepared

The psychophysics of imagery.

A series of experiments considers the extent to which the interrelations among subjective magnitudes aroused by images corresponds to those for subjective magnitudes aroused by physical stimuli. In Experiment 1,68 undergraduates typed phrases in response to graded categories regarding the imagined magnitude of lights, sounds, and smells. In Experiment 2,5 undergraduates and, in Experiment 3, 3 graduate students then magnitude estimated the image intensity aroused by each of these stimulus phrases. In Experiments 4 and 5, the same subjects performed cross-modality matches between phrases arousing images for different attributes (light, sound, and smell). Statistical analysis indicates that estimates based on images display many of the same patterns as those based on physical stimuli. The major exception involves sequence effects, present for actual stimuli but not for images.

Implementing a Standardized Safe Surgery Program Reduces Serious Reportable Events

BACKGROUND Patient safety in the perioperative period is essential for delivery of quality patient care. Mainstream quality organizations have implemented safe surgery recommended practices for ensuring patient safety. Effectively implementing safe surgery practices should result in a reduction in serious reportable event (SRE) rates. STUDY DESIGN This retrospective cohort study compared results before and after implementation of a standardized safe surgery program across a large health care system. Observational audits were performed to assure adoption of the new process. Serious reportable event rates (retained surgical item, wrong site, wrong patient, and wrong procedure) were tracked. Statistical analyses were performed on the SRE rate and days between SREs. RESULTS A total of 683,193 cases in the operating room and labor and delivery were evaluated over a 4-year period. The SRE rate before implementation was 0.075/1,000 cases and after implementation was 0.037/1,000 cases. There was a 52% reduction in the SRE rate (p < 0.05). The mean time between SREs increased from 27.4 days to 60.6 days (p < 0.05). Robotic and nonrobotic cases were affected equally; however, a significant difference in SRE rate persisted between robotic and non-robotic cases (p < 0.05). Robotic cases are 7 times more likely to incur an SRE. Audits demonstrated that the compliance rates for the program improved to 96% after complete system implementation. CONCLUSIONS An effectively implemented standardized safe surgery program results in a significant reduction in SREs. Robotic cases are at high risk for an SRE.

Human factors issues in the intensive care unit.

In the context of an aging population, more critically ill patients, and a change in intensive care unit (ICU) services stemming from advances in technology, prevalent medical errors and staff burnout in the ICU are not surprising. The ICU provides ample opportunity for human factors experts to apply their knowledge about the strengths and weaknesses of human capabilities to design more effective care delivery. Human factors experts design work processes, technology, and environmental factors to effectively and constructively channel the attention and behavior of those providing care; a few areas of focus can have marked impacts on care delivery and patient outcomes. In this review, we focus on these 3 areas and investigate the solutions and problems addressed by previous research.

Investigating Huds in Specialty Vehicles

Currently, several technologies are being integrated into a single system that provides the driver of a specialty vehicle with a virtual representation of the view out the windshield via a Head Up Display. As part of the development of this system, we are exploring human factors issues in a series of alternating simulation experiments and field studies. Here, we discuss a simulation experiment and a field study. In the simulation experiment, we compared the effectiveness of lane departure warnings given in three modalities—visual, auditory, and tactile (via the drivers seat). In the field study, we used a snowplow equipped with a Head Up Display, a Differential Global Positioning System, and digital geo-spatial databases. The participants were snowplow operators. The sessions that they participated were treated as a knowledge acquisition sessions. The information obtained during in this field study feed back into the next simulation stage of the program.

Perceiving emotions in robot body language: Acute stress heightens sensitivity to negativity while attenuating sensitivity to arousal

Abstract Reliance on socioemotional assistive robots is projected to increase, yet little is known about how our ability to perceive their emotional expression is impacted by psychological factors. In high-risk and high-tension domains such as emergency services and healthcare, how might the cognitive and physiological stress we are experiencing influence how we read a humanoid robots nonverbally conveyed emotions? Using a novel paradigm, we asked participants under experimentally-induced acute stress vs. low stress to evaluate a set of normed emotional body language poses conveyed by a physically-present vs. virtually-instantiated humanoid robot. Participants rated each pose for emotional valence (negativity/positivity) and arousal (calm/excited). Acute stress increased the perception of negative valence in negative high arousal poses, consistent with stress-induced hypervigilance. Surprisingly, stress diminished the perception of arousal in high arousal poses, whereas repeated presentation of the low arousal poses increased perception of arousal. Participants rated emotion similarly for the physically-present vs. virtually-present robot, although positively-valenced poses conveyed by the physical robot were perceived as more positive and more animate. We propose that perceptions of emotional arousal may be especially vulnerable to context effects and misattribution. These findings have implications for how assistive robots can best be designed for high-risk and high-tension contexts.

Implementing a Standardized Safe Surgery Program Reduces Serious Reportable Events: In Reply to Nathanson and Bloomstone

Loftus and colleagues recently examined whether a surgical checklist could reduce serious reportable events. Checklists as part of a safety protocol have become an important tool for improving patient safety in a surgical setting. They are inexpensive to implement and provide a structured, common-sense way for surgical teams to focus on safety issues. Although it is implausible that a checklist can do any harm, the expected benefits can vary across hospitals, and assessing efficacy can be a challenge for a variety of reasons. Loftus and colleagues assessed a checklist for rare, serious reportable events (SREs) (eg, wrong surgery on a patient, retained surgical items, etc) and found a 52% reduction in SREs when compared with a baseline population. Their results must be viewed cautiously due to the statistical methods they used. There was no attempt to adjust for surgical casemix, patient acuity, or robotic vs nonrobotic procedures, even though all of these confounding factors could affect the SRE rates and did vary within their patient population. They also used parametric inference methods (eg, t-test, z-test for proportions), even though the number of SREs was quite low and often <5 after the checklist was implemented. When modeling rare binary or count outcomes, more appropriate multivariate techniques include zero inflated negative binomial regression models and exact logistic regression, which allow for the adjustment of confounders. When comparing simple proportions, the binomial test or exact inference methods, such as Fisher’s exact test, should be considered. We also point out that this study only measured whether checklists were effective in reducing SREs. Assuming they are, it is then vital to continuouslymonitor SREs to guarantee that the surgical “process” is under control and the event rate is acceptably low. Regression modeling and statistical inference are not the tools to use for quality assessment after a checklist is implemented. Instead,we recommendhospitals use Statistical ProcessControlmethods, in particularG-Charts and scan statistics, when dealing with rare events like SREs. In addition, we recommend process-improvement specialists knowledgeable in both quality control and health care be involved for any patient-safety imitative and praise Loftus and colleagues for having an interdisciplinary team for their study.

Usability Evaluation of Electronic Health Record System around Clinical Notes Usage–An Ethnographic Study

Background A substantial gap exists between current Electronic Health Record (EHR) usability and potential optimal usability. One of the fundamental reasons for this discrepancy is poor incorporation of a User-Centered Design (UCD) approach during the Graphical User Interface (GUI) development process. Objective To evaluate usability strengths and weaknesses of two widely implemented EHR GUIs for critical clinical notes usage tasks. Methods Twelve Internal Medicine resident physicians interacting with one of the two EHR systems (System-1 at Location-A and System-2 at Location-B) were observed by two usability evaluators employing an ethnographic approach. User comments and observer findings were analyzed for two critical tasks: (1) clinical notes entry and (2) related information-seeking tasks. Data were analyzed from two standpoints: (1) usability references categorized by usability evaluators as positive, negative, or equivocal and (2) usability impact of each feature measured through a 7-point severity rating scale. Findings were also validated by user responses to a post observation questionnaire. Results For clinical notes entry, System-1 surpassed System-2 with more positive (26% vs. 12%) than negative (12% vs. 34%) usability references. Greatest impact features on EHR usability (severity score pertaining to each feature) for clinical notes entry were: autopopulation (6), screen options (5.5), communication (5), copy pasting (4.5), error prevention (4.5), edit ability (4), and dictation and transcription (3.5). Both systems performed equally well on information-seeking tasks and features with greatest impacts on EHR usability were navigation for notes (7) and others (e.g., looking for ancillary data; 5.5). Ethnographic observations were supported by follow-up questionnaire responses. Conclusion This study provides usability-specific insights to inform future, improved, EHR interface that is better aligned with UCD approach.

An assessment of currently available i.v. Push medication delivery systems

In 1999, a consensus conference evaluated the safety, simplicity of use, and cost of available i.v. medication delivery systems and the need for education and training of healthcare providers (HCPs).[1][1] The medication delivery systems evaluated included pharmacy-based i.v. admixture systems,