(See article by Leback et al, pages 841-848.)

Human factors is a discipline that utilizes the “understanding of interactions among humans and other elements of a system” and methods and design principles to “optimize the human well-being and overall system performance.” ¹ The field traces its origins to the study and design of human operator use of military systems and equipment. ² Human factors approaches to certain subtopics such as accidents, human error, and warning systems have been used to improve safety in industries including aviation, aerospace, transportation, and mining. The same principles and methods can also be applied to improving safety in healthcare systems, particularly as new technologies are incorporated into healthcare delivery, in the form of medical and surgical devices, health informatics, electronic medical record clinical decision supports, and health monitoring devices.

In this issue, Leback et alReference Leback, Johnson, Anderson, Rogers, Shirley and Safdar ³ describe results of injection-safety–focused observations and interviews conducted in a range of outpatient clinical settings within a single health system. Challenges to basic injection safety standards (eg, syringe reuse for >1 patient) persist in many healthcare settings,Reference Leback, Johnson, Anderson, Rogers, Shirley and Safdar ^{3 ,} Reference Kossover-Smith, Coutts and Hatfield ⁴ necessitating a thorough understanding of barriers to safe practices and innovative approaches to overcome such barriers, especially in outpatient clinics. Clinics in this study included adult and pediatric primary-care clinics, dialysis centers, urgent care clinics, imaging clinics, and outpatient procedure clinics. Observations of injection practices were conducted, and interviews of staff were also performed to understand barriers and facilitators to injection safety in the clinics. The authors utilized a human factors approach to evaluate interview responses and connected themes to the observation data. The Systems Engineering Initiative for Patient Safety (SEIPS)Reference Carayon, Schoofs Hundt and Karsh ⁵ framework was used to design interview questions and classify barriers and facilitators into the SEIPS categories of: workflow, persons, organization, environment, and tools and technology.

This study contributes several pertinent findings. First, generally good adherence to recommended safe injection practices was observed across clinics, including proper use of single dose vials (ie, 1-time use for 1 patient only). However, opportunities for improvement were identified, such as keeping multidose vials out of patient care areas and cleansing septa of vials prior to accessing. Second, according to the authors, the observations conducted in the study uncovered a greater number of gaps compared to routine infection prevention site visits of these same clinics that have relied upon self-reports of practice. This finding reinforces the importance of direct observations of practice as part of on-site assessments, which is a component of the CDC Guide to Infection Prevention in Outpatient Settings ⁶ and is essential to any evaluation of infection control practice.

Third, and perhaps most enlightening, is the analysis of the interview responses. For most SEIPS categories, roughly half of responses were coded as barriers. The exception was the tools and technologies category, for which only 27% of responses were barriers. All barriers were specifically reported as ones that make it difficult to give injections safely. The most frequently reported barrier, in any category, to giving safe injections was feeling rushed or high patient turnover. While perhaps not surprising, it should be alarming that staff across different clinic types reported this pervasive issue that has such potential to cause medical errors. Important barriers related to the environment were small patient-care areas and medication rooms, and an excessive distance between these 2 areas. Notable facilitators were the availability of injection supplies in work areas, and a commonly reported facilitator in the category of workflow was preparing medications in advance. The latter is a logical strategy to avoid errors when feeling rushed, yet it is at odds with recommendations to prepare medications as close in time as possible to their administration. This is particularly true if staff are engaging in batch preparation of medications for multiple patients, a practice that has contributed to outbreaks of infection.Reference Ross, Mehr and Carothers ^{7 ,} Reference See, Nguyen and Chatterjee ⁸ The Institute for Safe Medication Practices (ISMP) has recommended avoiding the need for vial manipulation and syringe preparation in the clinic setting through the use of manufacturer-prefilled or pharmacy-prepared prefilled syringes for i.v. push medications and flush. ⁹ When available, the use of “ready-to-administer” medications can save time, improve workflow, and reduce opportunities for errors and contamination. In this study, many of the reported barriers and facilitators across clinic types demonstrate that some measures intended to improve safety of practices (eg, separation of medication preparation and clean supplies from patient care areas) can create challenging workflows and result in (at a minimum) staff perceptions that the injections are less safe. An ideally designed system, environment, and work context would enable safe injections without hindering workflow.

In this way, the human factors approach mirrors a widely accepted hierarchy of public health interventions, in which a high likelihood of positive impact exists when the individual’s context can be modified so that default decisions align with healthy and desired actions (eg, those that promote injection safety) and when the effort level required by an individual (eg, to check a medication vial expiration date) is lowest.Reference Frieden ¹⁰ In contrast, education and training, which are often the focus of infection prevention interventions, are less likely to result in positive or sustained impact in the absence of other interventions that address broader systems issues.Reference Frieden ^{10 –} Reference Wong ¹²

The human factors approach as applied for the purpose of infection prevention and control has advantages and disadvantages (Table 1). The most compelling advantage is the potential to identify major underlying causes and contributors to a problem. Just as Leback et al discovered that feeling rushed might have a more powerful influence on practices than injection safety knowledge, training, supplies or technology, there are opportunities to gain important insights into why lapses in other important infection prevention practices can occur, and how to intervene. This approach considers multiple broad outcomes simultaneously and assumes that staff engagement and job satisfaction are integrally linked to positive organizational outcomes (ie, recognition and profitability) and health and safety outcomes such as healthcare-associated infections (HAIs).Reference Carayon, Schoofs Hundt and Karsh ⁵ The idea that improvements in staff well-being can serve as a “rising tide” to positively affect other outcomes in healthcare has obvious merits.

Table 1

Human Factors Approach to Infection Prevention

The human factors approach has 2 potential disadvantages: its resource-intense nature and generalizability of evaluation findings and solutions. Detailed evaluations can be expensive and time-consuming, and ready solutions to certain issues, such as physical infrastructure, staffing, or workload, might not exist. Human factors experts with experience in healthcare are not available to every healthcare system,Reference Hettinger, Fairbanks and Hegde ¹¹ and they might not be available at all to freestanding clinics that lack hospital affiliation. Because human factors assesses the interactions among humans, technology, and environments within systems, these factors can all differ in each clinic, hospital unit, or other local healthcare setting, the generalizability of research findings is potentially undermined. Despite this, Leback et al identified common themes across different clinic types, and it is possible that some settings (eg, outpatient dialysis clinics with shared corporate ownership) might have many more similarities than differences in factors such as tasks, environments, technology, and organization.

Strategies based upon human factors principles have long been employed in the field of infection prevention. Checklists, implementation bundles, and other tools have been famously adopted and incorporated as staples of device-associated infection prevention.Reference Berenholtz, Pronovost and Lipsett ^{13 – 15} Communication tools, strategies and technologies are also in use to improve the transfer of information that is essential to infection control or antimicrobial stewardship.Reference Trick, Lin and Cheng-Leidig ^{16 –} Reference Morton, Curzake, Morrill, Parente, Gaitanis and LaPlante ¹⁸ Usability testing of the human-machine interaction is conducted by manufacturers of reprocessing machines or environmental disinfection devices. In addition, efforts exist to integrate infection prevention considerations into healthcare facility design, albeit largely focused on hospital settings.Reference Zimring, Denham and Jacob ¹⁹ Collaborations between healthcare epidemiologists and human factors engineers, and inclusion of human factors experts in infection prevention and control efforts, appears to be a more recent phenomenon. Rock et alReference Rock, Cosgrove and Keller ²⁰ utilized the SEIPS model and conducted a human factors evaluation to discern opportunities to improve environmental cleaning and disinfection of patient rooms. The evaluators identified multiple strategies in the domains of persons, tasks, organization, environment, and tools and technology that could result in desired improvements to patient room disinfection. The human factors and systems engineering approach has also been utilized to conduct several other evaluations of barriers and facilitators to infection prevention practices (eg, hand antisepsis and C. difficile prevention) and clinical guideline adherence.Reference Schwartz, Schmitz, Safdar and Pop-Vicas ^{21 –} Reference Yanke, Carayon and Safdar ²³ In these examples, human factors has advanced our knowledge of why and how systems, and the humans operating within those systems, fail to prevent HAIs. What is needed now are additional demonstrations that such findings can directly inform strategies and interventions that positively impact primary outcomes, such as HAIs or antimicrobial resistance.

Adherence to standard practices and interventions that have been shown to prevent infections in healthcare settings remains a critical challenge. The work done by Leback et al extends the science of human factors and systems engineering to outpatient settings, where adherence gaps may be greatest, and it highlights the promising nature of these approaches for improving patient care and outcomes. Ultimately, the value of human factors approaches to infection prevention will depend on the ability not only to just identify and describe challenges to best practice but also to successfully overcome challenges through effective interventions that improve adherence and reduce HAIs.