Rebooting Value: Part 2 Human Factor Engineering and Manufacturing Processes

Swiss Cheese Model…we don’t talk about this enough

In Part 1 of Rebooting Value we raised the flag about the number of new medical device approvals and the number of medical device recalls in 2020. In Part 2 we will re-emphasize the continued diligence for medical device users [provider, patient, family etc.] to be active participants in human factor engineering-HFE aka Usability Testing. Both the User and Manufacturer play significant roles in assuring new medical devices or modified devices are performing as they are intended to by design to deliver safe, high quality care at an affordable cost. HFE in its simplest form is to “model the interactions between a user and a device, the processes performed by each and the user interface between them”- FDA CDRH- “Applying Human Factor and Usability Engineering to Medical Devices” Guidance Document.

Key design elements in HFE analysis involve the device user, the use environment and the user interface. Manufacturers are asked to emphasize HFE testing for premarket submissions using FDA Guidance Documents including, at minimum, for the original 16 device categories deemed to have a clear, potential use error risk. Based on personal experience monitoring internal and external safety reports for >20 years the device list is substantially longer than the original 16 and should be more inclusive of the 3 classes of medical devices. Nursing has long been a proponent of usability testing as it assessed their care practices especially when using devices. They need to be involved in designing new devices and how to incorporate them into their complex work stream and to use prevention techniques on devices already in use-https://www.myamericannurse.com/nurses-mitigate-device-safety-hazards/ . I had the privilege participating in a group project that included nurses from education, regulatory and practice that created an easy to follow risk based training tool for medical devices modeled on four categories; potential for patient or staff harm, potential for tubing misconnections, practice or procedure change and complexity. Responses to predefined choices were scored and totaled to determine the level of training; ranging from a score of 4 or less an announcement was sufficient to a score of 15 or more which required a needs assessment, trainers, in-servicing, competencies, demonstration of use, etc. The higher the risk score the more layers it required.

This is where we bring in the intersection of value for HFE where risk management, safety, quality and costs all converge into this critical concept. You may recall the Swiss Cheese Factor that visually emphasizes the premise that adverse outcomes result from a combination of systemic issues; resource availability, organizational policies and procedures, and human functional errors. Every layer of defense against errors has holes however as you add layers the smaller the risk of harm ergo less chance of the holes lining up to allow an error to occur. By looking inwardly at your organization consider the effectiveness of your safe reporting system and if you have a robust root cause analysis process to analyze the layer where holes occur and how to repair them. This is a high level look at LEAN where the error reflects on issues at the systems level not the human level.

You might ask yourself how do we calculate value. You are now at the crucial intersection - user costs for poor quality and outcomes and manufacturer costs for risk and quality modeling. A critical element of the manufacturers financial model is the total cost of quality incurred to operate while maintaining the function of quality in their business. They use processes to measure what resources will be used and how they are used for product assurance. There are Good Quality costs [inspections, calibrations, auditing, risk management, quality planning, capability studies and training] and Poor Quality costs [ rework, scrap, corrective actions, material review boards, product returns, customer complaints, corrective/preventive actions and recalls]. Some studies report manufacturer costs of quality in the US range from 20-35% of sales and 10%-20% of revenues. Investing in good quality costs to maintain outgoing quality levels can make a positive impact to their bottom line, help to distinguish competitive advantage and reduce potential failures- think the Swiss cheese example. Manufacturers balance the risk controls with the costs for desired quality through the entire product life cycle. Delay of product launch and suboptimal risk mitigation can be remedied by early clinical and product design risk, use of more upstream processes rather than waiting to inspect post production, decreasing manual controls and making manufacturing less complex.

It is at this juncture the term intersection truly resonates. Foremost among all of the processes and balancing a manufacturer performs to create a product the most import of these are to understand the customer needs and proactively obtain feedback. How we know that these are critical is to synthesize that the world’s patient safety and risk management software market is expected to grow from $1.3B in 2019 to $2.2B by 2024. Not all of this increase is due to managing medical device events in the user environment but also focuses on a variety of medical errors, compliance, operational efficiencies and controlling HACs-hospital acquired conditions.

Check back next week as I deconstruct processes using Reverse Value Analysis.