A known use error (German: bekannter Anwendungsfehler) denotes an error already observed or documented in the use of a medical device that has occurred with the manufacturer's own medical device, a predecessor product, or a sufficiently comparable product. It can be part of a foreseeable sequence of events and contribute to a hazardous situation or harm, but does not necessarily have to.
The findings typically come from complaint data, vigilance reports, recalls, usability studies, literature sources, or experience with predecessor and competitor products, and serve as an important input to the use-related risk analysis.
Importance in the usability engineering process
The analysis of known use errors usually takes place early in the usability engineering process. The aim is to systematically identify already known weaknesses of similar user interfaces before they occur in the manufacturer's own product. This allows risks to be addressed proactively instead of being discovered only in formative or summative studies. The findings are reconciled with the use specification and feed in particular into the task analysis and the use-related risk analysis (URRA); however, they are not automatically part of the use specification themselves.
Distinction from malfunctions and deviations in use
A use error exists when the actual result of use deviates from the intended result, without necessarily involving a technical malfunction of the product. The cause may lie, for example, in a misleading display, unsuitable operating logic, or an error-prone work environment. Known use errors must therefore be distinguished from technical defects, software errors, or hardware failures.
Identifying known use errors
Typical data sources are the FDA MAUDE database (the FDA's database of adverse event reports for medical devices), complaint and vigilance data, recalls and field safety corrective actions (FSCA), findings from human factors studies, user feedback, literature and case reports, as well as experience with predecessor models and competitor products. Merely collecting events is not sufficient, however. The data must be analyzed with regard to their use-related causes in order to distinguish actual use errors from technical problems.
Known use problem summary (KUPS/KUES)
In regulatory practice, a known use problem summary (KUPS) or known use error summary (KUES) is often prepared. This document summarizes known use-related problems of similar products in a structured way. Typical contents are a description of the event, the context of use, the affected user group, the impact, and possible causes in the user interface. KUPS and KUES are document names that are common in practice but not prescribed by any standard. What matters is not the document title but a traceable search, assessment, and transfer of the results into the risk analysis.
Connection to the use-related risk analysis
Known use errors are important input data for the URRA. They help to identify potential use errors, hazardous situations, and hazard-related use scenarios and to derive suitable risk control measures. Particularly valuable are known use errors that have already led to harm or near-harm under real conditions of use. These often provide indications of risks that have so far been underestimated.
Common weaknesses in practice
Many manufacturers limit their research to internal complaints or a superficial search in public databases. As a result, relevant findings from comparable products remain unconsidered. Also problematic is the blanket adoption of event reports without analysis of the actual use-related causes. A regulatorily robust approach documents both the research methodology and the rationale for why certain known use errors are or are not relevant for the manufacturer's own product.
Regulatory reference
IEC 62366-1 requires that known hazards and hazardous situations of existing user interfaces of similar medical devices be taken into account as an input to the usability engineering process. In its human factors guidance, the FDA expects known use-related problems of comparable products to be considered in the development and evaluation of medical devices and describes corresponding expectations in its human factors submission reports as well. ISO 14971 requires the use of available information from similar products and post-market data to identify hazards and hazardous situations. Taking known use errors into account can be part of this requirement.
Known use errors of similar products are one of the least expensive ways to address risks proactively rather than reactively. A robust KUPS/KUES search combines several sources and assesses the actual use-related causes instead of adopting events uncritically.
Frequently asked questions (FAQ)
Does every known use error of similar products have to be adopted?
No. Relevance, context of use, user groups, operating concept, and risk profile must be assessed. Use errors that are not relevant should be excluded with a traceable rationale.
Are MAUDE reports alone sufficient?
No. MAUDE is an important source but often provides incomplete information. A robust analysis combines several data sources and assesses the actual use-related causes.
Is a known use error automatically a critical task?
No. A known use error can point to a critical task. Whether a task is critical, however, is decided solely by the severity of the harm that could result from incorrect or omitted performance.
Can known use errors from competitor products be used?
Yes. Competitor products in particular are valuable sources for recognizing known weaknesses of user interfaces early and deriving corresponding countermeasures.
Do you want to research known use errors of comparable products systematically and embed them in your risk analysis? We support you throughout the usability engineering process according to IEC 62366-1.
More about our usability engineeringSources
- IEC 62366-1:2015+AMD1:2020, Medical devices, Part 1: Application of usability engineering to medical devices
- ISO 14971:2019, Medical devices, Application of risk management to medical devices
- FDA MAUDE, Manufacturer and User Facility Device Experience Database