Vredenburgh & Zackowitz, Inc.

Human Factors, Ergonomics, Safety,
Engineering & Organizational Consulting


Healthcare Worker and Patient Safety


Vredenburgh, A.G., Sunderman, G.L., Daly Guris, R.J., & Cheruku, S.R. (2021). Epidemic Response: Follow-up and lessons learned from the US response to the evolving and conflicting risk information, focusing on education and clinical environments. In Proceedings of the Human Factors and Ergonomics Society Annual Meeting, vol. 65, 1: pp. 1584-1587.

In this follow-up panel, we discuss what we have learned over the last year about responding to an epidemic or pandemic that has demonstrated a level of transmission unprecedented in the modern era. Two medical doctors that have worked on the front of this pandemic share their experiences transitioning from the “sharp end” of the response. Decisions about how to mitigate hazards have occurred at the personal, institutional, and health policy levels, in real-time, with frequent adaptation, and often in advance of concrete evidence. Over the course of the pandemic, hospital systems revised existing protocols to manage perceived risks in real time using emerging information from other centers. With the introduction of vaccines, there is a new type of risk perception. Is the vaccine perceived to be safe? Is there a disparity in perception among different population groups? That said, analyses are also complicated by emerging viral mutations with unclear implications. What factors increase or decrease public compliance with precautions? How are US education policymakers deciding about face-to-face classroom instruction? This panel includes a warnings expert, an expert on education policy, and two practicing physicians.

Vredenburgh, A.G., Welner, KG., Daly Guris, R.J., & Cheruku, S.R. (2020). Epidemic Response: How to evaluate and respond to evolving and conflicting risk information with a focus on education and clinical environments. In Proceedings of the 2020 HFES 64th Annual Meeting, Santa Monica, CA: Human Factors and Ergonomics Society, 1732-1735.

By October, we will have learned a great deal about responding to an epidemic or pandemic that has proved to have a level of transmission unprecedented in the modern era. The possible and likely responses include many unknowns. Coordinated and collaborative implementation has been complicated by conflicting information from multiple governments and organizations in several languages. What will we learn about how the United States can improve its ability to respond? How do we develop consistent and accurate warnings and messaging to the public in order to increase compliance regarding a new, and not well understood, epidemic? What factors increase or decrease compliance? How are US education policymakers deciding about face-to-face instruction? How have physicians and hospitals adapted their workflows in the face of uncertainty and supply chain inconsistencies? This panel will include a warnings expert, an expert on education law and policy, and two physicians.

Bench, M.L., Vredenburgh, M.J., Zackowitz, I.B. & Vredenburgh, A.G. (2017). An epidemiological perspective of individual and population health risk prevention. Pedro Arezes (ed.), In Advances in Safety Management and Human Factors, (pp. 357-368). Warsaw, Poland: Springer International Publishing.

Several distinct but intrinsically related sections are discussed from an epidemiological standpoint including the epidemiology of risks, individual versus population risks, intervention and prevention. A number of specific risk factors identified in published research are considered and categorized for either individual or population-level effect. Risk factor assessment, with an emphasis on the concept of risk level among individuals through their life span is specified, with a focus on consumption patterns. The efficacy of prevention is evaluated among intervention approaches, with case studies provided for context.

Vredenburgh, M.J. (2009). Public Health: An Epidemiological Study to Explore the Relationship between Literacy, Language, Aging, and Familiarity on Comprehension of Health Information. In Proceedings of the Human Factors and Ergonomics Society. (pp. 744 – 748). Santa Monica, CA: Human Factors and Ergonomics Society.

Studies concerning health literacy indicate that health-related materials cannot be understood by most of the people for whom they are intended. A primary aim of the current study was to evaluate the extent to which medication information sheets effectively convey instructions and health information to populations who may be at risk of making errors: seniors (65+), new and inexperienced medication users (ages 16-21), and English learners. An “experimental” information sheet was created for this study by reformatting existing sheets to comport with results of my prior science fair research. A comprehension test was also created for this study. Two existing information sheets (one commonly used by pharmacy chains and one by the U.S. Food and Drug Administration [FDA]) were compared to the experimental sheet using a mixed-model ANOVA. Results indicate that the young, inexperienced users and seniors performed significantly better when tested using the reformatted, experimental sheet. Since seniors use significantly more drugs, and the more drugs taken the greater risk of misunderstanding instructions, it is critical that these sheets are redesigned to be usable by this population group.

Vredenburgh, A.G., & Zackowitz, I.B. (2009). Drug Labeling and its Impact on Patient Safety. In Sonja Koneczny (Ed.), WORK: A Journal of Prevention, Assessment & Rehabilitation, Volume 33, Number 2. (pp. 169-174). The Netherlands: IOS Press.

Adverse drug events (ADE) are defined as any medication error with significant potential to harm a patient (Fortescue et al, 2003). Often times, ADEs occur due to inadequate or ineffective systems of labeling. These ADEs often result in mistakes in prescription adherence (compliance) with the prescription instructions. These mistakes are costly and can be deadly. Potential problems with drug labeling can occur in both in-patient and out-patient environments. This paper discusses some of the key issues to consider in drug labeling and its impact on patient safety.

Vredenburgh, A.G., Kalsher, M.J., & Vredenburgh, M.J. (2006). Evaluating hazard communication of patient medication information sheets for prescription drugs. IEA2006: 16th World Congress on Ergonomics. Elsevier Ltd.

The US Food and Drug Administration requires that pharmacies provide patient medication information (PMI) sheets describing usage and hazard information to recipients of the prescription drugs that they dispense. These PMI sheets are required to be understood at a 6th grade reading level (the standard for patient education materials). All medications have risk associated with their use. It is important for patients, physicians and pharmacists to have enough information to decide whether the benefits of taking a medication outweigh the risks.

Murphy, W.H. Vredenburgh, A., Weinger, M.G., Yoshida, D. (2005). Human factors engineering, legal liability, malpractice, and patient safety. In Human Factors, Ergonomics, and Patient Safety for medical Devices. Arlington, VA: Association for the Advancement of Medical Instrumentation (AAMI).

Vredenburgh, A.G., Longden, S., Williams, K.J., & Kalsher, M.J. (2005). Evaluating latex glove container warnings in a realistic setting. International Journal of Industrial Ergonomics, 35, 559-568.

Healthcare workers sometimes develop severe hypersensitivity to products containing latex. This study evaluated three label configurations designed to alert users to the risks of latex exposure. Results included evidence of an industry-wide lack of knowledge regarding latex hypersensitivity. The explicit warning was most effective in alerting participants to the hazard. Relevance to industry: The informational component of warnings labeling is particularly critical for apparently benign products, such as latex gloves, that bear a hidden hazard. Warnings increase the probability that glove users exercise appropriate precautionary behavior when they encounter medical products and instruments that contain natural rubber latex in the workplace.

Vredenburgh, A.G. & Weinger, M.B. (2004). Communication of drug hazard information: A critical analysis of how the relationship between the pharmaceutical companies, the FDA, clinicians and patients impacts patient safety. In Proceedings of the Human Factors and Ergonomics Society 48th Annual Meeting. Santa Monica, CA: Human Factors and Ergonomics Society, 2040-2044.

Adverse drug events (ADE) are common, costly, and responsible for significant morbidity and mortality among hospitalized patients. They are a leading cause of death, accounting for up to 106,000 American deaths annually. Our healthcare system relies on accurate reporting of ADE by clinicians to the pharmaceutical companies, and by the companies to the FDA. The system also relies on the pharmaceutical companies providing accurate and complete warnings and contraindications to physicians and patients. Frequently, however, these risks are not effectively communicated to those who prescribe and take the medications. A critical evaluation of the American drug hazard management system reveals several factors that contribute to these shortcomings and therefore impact patient safety. These system components interact to increase the probability of adverse drug events and accordingly, impact consumer safety.

Vredenburgh, A.G. & Weinger, M.B. (2004). Examination of apparent flaws in the American drug hazard detection, evaluation, and risk communication system. Abstract in the Program of the Second Annual Patient Safety Conference: Making care safer one patient at a time. San Diego, CA, 100.

Approximately 100,000 Americans die annually from adverse drug events (ADE). Yet, physicians, pharmacists and patients are often unaware of the risks associated with many medications. Our healthcare system relies on accurate reporting of ADE by clinicians to the pharmaceutical companies, and by the companies to the FDA. The system also relies on pharmaceutical companies providing complete and accurate risk information to clinicians who must then inform their patients. We hypothesize that our system to assess and communicate medication risk is defective and may actually increase the probability of ADE. Conflict of interest is a major problem. Manufacturers want to bring their drugs to market as quickly as possible leading to a bias to study as few patients as necessary to prove a benefit. As a result, most pre-market studies are insufficiently powered to detect less common ADE. Officially sanctioned medication information like the FDA-approved drug package inserts often contain misinformation, outdated information, and omissions. However, the content of these materials, initially prepared by manufacturers, is the result of complex negotiations during the drug approval process. While FDA oversight insures a minimal level of accuracy, anchoring and other biases can be expected given the manufacturer’s financial motivations. Post-market surveillance of drug risks relies primarily on voluntary reporting of ADE. However, voluntary reporting captures only a small proportion of actual ADE for a variety of reasons. Clinicians often have difficulty associating adverse events with specific drugs in individual patients given multipharmacy, underlying disease or other concurrent factors. There are no incentives to report ADE. In fact, there are strong financial, regulatory, and medicolegal disincentives for clinicians, hospitals, and manufacturers. Pharmaceutical sales representatives, known to be the primary source of drug information for about half of all physicians, also have conflicting responsibilities: to sell their drugs and to educate clinicians about those drugs, including risk information. Over-worked clinicians may forget to communicate effectively known risks to patients. These myriad flaws in our drug hazard management and communication system, which interact to increase the probability of ADE, must be addressed.

Vredenburgh, A., Weinger, M., Macario, A., & Smith, B. (2000).  Developing a technique to measure anesthesiologists’ real-time workload. In Proceedings of the XIVth Triennial Congress of the International Ergonomics Association and 44th Annual Meeting of the Human Factors and Ergonomics Society. Santa Monica, CA: Human Factors and Ergonomics Society, 4-241 – 4-244.

Workload is a construct used to describe the extent to which an operator has engaged the cognitive and physical resources required for task performance. As task difficulty increases, operators allocate more resources to maintain acceptable performance. The purpose of the present study is to develop a technique to measure workload continuously, with high-resolution in real-time, and in a way that accounts for the contribution of multiple individual task components of the job of administering anesthesia. Workload associated with 51 clinical tasks performed by anesthesiologists was assessed using a written survey instrument developed for this study. Participants were 241 anesthesia providers. Interval scale values were computed for each of the tasks using direct estimation procedures. These values were then used to produce workload density maps for actual anesthesia cases by weighting the tasks performed during the case by their workload scale values. Moment-by-moment data on the specific tasks performed by anesthesiologists were obtained in real-time by trained observers during actual anesthetic cases. This type of analysis can be used to evaluate the costs associated with technical anesthesia procedures increase our understanding of the anesthesiologists’ job, and guide rational optimization of procedures, equipment, scheduling and training.

Weinger, M.B, Vredenburgh, A.G., Schumann, C.M., Macario, Williams, K.J., Kalsher, M.J., Smith, B., Truong, P.C., & Kim, A. (2000). Quantitative Description of the workload associated with airway management procedures. Journal of Clinical Anesthesiology, 12(4), 273-82.

STUDY OBJECTIVES: To measure the workload associated with specific airway management tasks. SETTING AND INTERVENTION: Written survey instrument. PATIENTS: 166 Stanford University and 75 University of California, San Diego, anesthesia providers. MEASUREMENTS AND MAIN RESULTS: Subjects were asked to use a seven-point Likert-type scale to rate the level of perceived workload associated with different airway management tasks with respect to the physical effort, mental effort, and psychological stress they require to perform in the typical clinical setting. The 126 subjects completing questionnaires (overall 52% response rate) consisted of 43% faculty, 26% residents, 23% community practitioners, and 8% certified registered nurse-anesthetists (CRNAs). Faculty physicians generally scored lower workload measures than residents, whereas community practitioners had the highest workload scores. Overall, workload ratings were lowest for laryngeal mask airway (LMA) insertion and highest for awake fiberoptic intubation. Airway procedures performed on sleeping patients received lower workload ratings than comparable procedures performed on awake patients. Direct visualization procedures received lower workload ratings than fiberoptically guided procedures. CONCLUSIONS: These kinds of data may permit more objective consideration of the nonmonetary costs of technical anesthesia procedures. The potential clinical benefits of the use of more complex airway management techniques may be partially offset by the impact of increased workload on other clinical demands.

Vredenburgh, A.G., Saifer, A.G., & Cohen, H.H. (1995). You are going to do what with that thing? An ergonomic analysis of a medical device. Ergonomics in Design, April, 16-20.