Known usability problems (German: bekannte Gebrauchstauglichkeitsprobleme, also known as known use problems) are documented problems, use errors, use difficulties, or use-related hazards that are already known from predecessor products, similar products, vigilance data, market surveillance, literature, complaints, service reports, or earlier usability studies. In the usability engineering process, they serve as a systematic source of information to identify potential use errors early and to incorporate them into the design of the user interface and the use-related risk analysis.
A known use error is only one possible form of a known use problem. The umbrella term also includes use difficulties, close calls, and problematic features of the user interface, without a concrete error having to be documented already. The term known use problems comes from the FDA Human Factors Guidance. IEC 62366-1 instead speaks of known or foreseeable hazards and hazardous situations.
Role in the usability engineering process
Evaluating known usability problems is part of the usability engineering process according to IEC 62366-1, which requires the identification of known or foreseeable hazards and hazardous situations for this purpose. The goal is not to rely exclusively on newly collected user data but to systematically evaluate existing knowledge. This makes it possible to recognize recurring patterns of use errors early. The activity particularly supports the identification of hazards, hazardous situations, and potential use errors.
Typical sources
Important sources are CAPA systems (corrective and preventive action), complaint databases, vigilance reports, PMCF and PMS data (post-market clinical follow-up and post-market surveillance under the EU MDR), service reports, recall information, scientific literature, formative studies, and findings from predecessor products. Publicly available databases such as the FDA MAUDE database can also provide relevant information. For platform products or product families, findings from technically related systems should be considered. The traceability of the source selection should be documented.
Distinction from use errors and use difficulties
A known usability problem is not a separate error category but an observation or a source of knowledge. The problem can manifest itself, for example, as a use error, a use difficulty, a close call, or an actual harm event. In practice, these terms are often mixed up. For the analysis, however, it is crucial to understand the underlying weakness of the user interface and not merely to document the observed symptom.
Typical examples
Frequently occurring usability problems include:
- Confusion of similarly designed controls
- Misinterpretation of alarm messages
- Incorrect parameter entries due to ambiguous displays
- Confusion of connectors or consumables
- Errors during device preparation or setup
- Misunderstandings caused by unclear instructions for use (IFU) or labeling
- Overlooked status indicators
- Incorrect operation under stress or time pressure
Such problems can recur if known causes are not recognized or addressed.
Influence on risk analysis and evaluation
Known usability problems should flow directly into the use-related risk analysis. They can be a reason to derive additional hazard-related use scenarios or to select certain scenarios for formative and summative evaluations. If known problems are ignored, there is a risk that critical use scenarios will not be tested in the later validation. In audits and notified body assessments (notified bodies are independent conformity assessment bodies under the EU MDR), it is often questioned how known findings were systematically taken into account.
Common weaknesses in practice
A common mistake is to evaluate only internal complaint data and to leave external sources unconsidered. Equally problematic is the assumption that a lack of complaints automatically means there are no usability problems. Known problems are also often merely collected, without documenting in a traceable way their influence on design decisions or test planning. This creates a gap between gathering information and actual risk control.
Regulatory reference
IEC 62366-1 requires in the usability engineering process that the manufacturer identify known or foreseeable hazards and hazardous situations, taking into account existing knowledge from available sources; known usability problems from predecessor products, literature, market surveillance, and similar sources are to be used as input information for deriving use-related risks. Under ISO 14971, information from production and the post-production phase is to be included as input to risk management; for use-related risks, this also includes findings about use errors and use problems. The EU MDR requires in Annex I that risks due to ergonomic features and foreseeable use errors be reduced as far as possible. Knowledge about known use problems supports the demonstration of this requirement.
Known usability problems are not a nice-to-have but a required input to the usability engineering process. Those who restrict themselves to internal complaint data regularly overlook the most valuable insights from predecessor and competitor products.
Frequently asked questions (FAQ)
Do known usability problems have to be considered only for predecessor products?
No. The analysis should also cover similar products, competitor products, literature sources, vigilance data, and other external sources of information. The focus is on the transferability of the findings to the product under consideration.
Is a complaint evaluation sufficient as evidence?
As a rule, no. Complaints reflect only part of the available knowledge. For a robust analysis, additional data sources should be considered.
Are known usability problems automatically critical tasks?
No. They are initially indications of potential risks or use difficulties. Only further analysis decides whether critical tasks or hazard-related use scenarios arise from them.
What do auditors or notified bodies typically expect?
Typically, they expect the sources to be documented in a traceable way and it to be evident how the findings gained flowed into risk management, design decisions, and evaluation planning.
Do you want to research known usability problems systematically and integrate them into your use-related 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
- Regulation (EU) 2017/745 on medical devices (MDR)
- FDA Guidance: Applying Human Factors and Usability Engineering to Medical Devices
- FDA MAUDE, Manufacturer and User Facility Device Experience Database