Designing a safer “choice architecture”

Nudge theory argues that people have a fast-thinking system that makes rapid automatic-seeming judgments based on the specific choices provided to them and the way those choices are structured in a “choice architecture.”Reference Thaler, Sunstein and Balz ¹¹ Holding all else equal, if choices are open to quick action, people will often opt for the action with the least effort.Reference Thaler, Sunstein and Balz ¹¹ Everyone is familiar with check-out lines at supermarkets where high-margin candy beckons while waiting in line, giving the hungry shopper the opportunity to impulsively buy and snack. Similarly, in a biocontainment unit, nudges can be provided that move HCWs toward following a safe protocol automatically. If a hand hygiene opportunity is within the narrow visual field during movement into a patient room, hand hygiene compliance increases.Reference Nevo, Fitzpatrick and Thomas ¹²

In the simulations, we observed that HCWs would occasionally step out of the doffing area once they started the process of removing the PPE and go back to the areas considered to be highly contaminated to reach for the tools, throw away trash, or clean their hands. The default presented the HCW was to step out of the designated doffing area because of the location of the trash receptacle, hand sanitizer dispensers, etc. Behaviors such as throwing away trash are automatic behaviors for most people and overcome more deliberative thinking. The environment supports safe automatic behavior when training and mental models align with cues (eg, when there is only one natural place to put trash).

These nudges can be restructured into an overall safer “choice architecture”Reference Thaler, Sunstein and Balz ¹¹ where the default choices are the safest. These nudges can be suggestive in the sense that they help channel behavior among a range of available choices, such as providing a green, yellow, or red color-coded floor covering that suggests where to stand during clean, transitional, or potentially contaminated phases of doffing.Reference Herlihey, Gelmi, Cafazzo and Hall ¹³ They can also be more directive, such as a biocontainment unit that only has a single directional flow of movement from a clean or “cold” zone to a transitional or “warm” zone to a contaminated or “hot” zone.Reference DuBose, Matic and Wong Sala ¹

Reducing the cognitive load of the individual HCW

A choice architecture that has physical cues that nudge toward safe behavior reduces cognitive load by helping HCWs automate otherwise individual actions. Visual cues within line of sight (eg, doffing mirrors) and providing supplies or equipment within reach (eg, hand hygiene dispensers) can reduce what the HCW needs to remember and plan. In addition, specific information, such as checklists, signs, and digital displays, can be moved to the built environment.

Safe doffing requires cognizance of location in space and background activity in the doffing zone and patient room. The HCW needs to be aware of what he or she is doing and what is going on in the doffing area and potential contamination, as well as remain alert to the state and needs of the patient. This high level of situational awareness increases the cognitive load on the HCW. Understanding and processing this information depends on a shared understanding of the protocol and each role by the HCW and the TO. It also requires a physical setting that provides access to information about the HCW’s PPE in the doffing area and in the patient room.Reference Endsley ¹⁴ Good situational awareness is potentially supported by shared visual and auditory information; good visibility of the clean, transitional, and potentially contaminated zones; shared information about how each doffing step is progressing; and the ability to respond to unexpected lapses in doffing, such as quickly noticing tears in the HCW’s PPE.

Focusing on the role of the built environment during brief “infectious risk moments”

A challenging aspect of doffing is that infection risks are often caused by brief events such as a spill, touching a surface, or touching the HCW’s skin. These might be so fleeting as to avoid notice. We have adopted an approach similar to what Clark et alReference Clack, Schmutz, Manser and Sax ¹⁰ describe as “infectious risk moments,” viewing infection prevention and risk as noncontinuous. Whereas the design of a biocontainment unit must accommodate many care processes, in the PEACH simulations, we sought to identify (1) specific doffing steps or behaviors that increase the risk for cross-contamination and self-contamination, (2) how often they occur, (3) where and when they happen, and (4) what environmental characteristics influence them. This attention to “moments” helps narrow the considerations for design by helping direct where nudges, choice architecture, moving cognition into the physical setting, and improving situational awareness need to be focused. The human factors team identified these moments by observing behaviors in doffing that might increase the risk of contamination. By carefully analyzing the incidence of these behaviors and their potential impact on infection, the team was able to quantify these moments.Reference Mumma, Durso and Ferguson ⁵ In addition to the list of “risky behaviors” identified by the human factors team, the design team expanded the list to include the actions of participants that were seen as the result of the built environment failing to support a safe doffing process. They asked how specific environmental qualities such as the location of hand hygiene dispensers or trash bins could impact these specific behaviors.

Based on the results of this research, we are currently conducting a follow-up study to test refined prototype designs of the doffing area in biocontainment units on subjects who are not HCWs and have no prior PPE training. We are focusing on the importance of zone demarcation and color coding, on the use of balance-aide tools, and on providing fixed location of mobile items and equipment in relation to the cognitive load on the individual HCW. The prototype of improved design will be tested on 10 trained HCWs.

We found that a multidisciplinary team including healthcare epidemiologists and evidence-based design researchers can create a system that can potentially make doffing easier and safer. Safe doffing depends not only on training and practice of HCWs but also on a built environment that is part of a system of safe care that supports rather than impedes safety by reducing effort and making safe behaviors automatic and natural. This multidisciplinary collaboration can be aided by a common framework—in this case, by focusing on the choice architecture, moving knowledge to the built setting, and focusing on risky moments—and by empirical observations that make the invisible impediments to safe care visible. This framework should be expanded to address other serious communicable diseases and to more routine patient care that involves infection precautions, to improve HCW safety, and to help deliver better, safer patient care.