Labeling (German: Kennzeichnung) comprises all information provided to a user on or together with a medical device: product labels, packaging markings, symbols, warnings, and the instructions for use. From a human factors engineering perspective, labeling is part of the user interface and is therefore itself subject to usability assessment, not merely a mandatory regulatory document.
Labeling as part of the user interface
In its 2016 human factors guidance, the FDA counts not only controls and displays as part of a medical device's user interface but explicitly also packaging, labeling including the instructions for use, and training. IEC 62366-1 likewise requires that information for safety be subject to the usability engineering process and be evaluated for perceptibility, comprehensibility, and support of correct use. Labeling is thus not merely a regulatory document but an interface between user and product: If safety-relevant information is hard to find, hard to understand, or presented in a misleading way, this is a human factors problem and can lead to a use-related risk.
Even a technically flawlessly developed medical device can cause risks if users do not find important information, do not understand it, or interpret it incorrectly. Faulty or misleading labeling is among the most frequent causes of use errors and can directly affect patient safety.
Which information belongs to labeling?
Depending on the product type, this includes, among other things: product identification (product name, variant, model designation, UDI, the unique device identifier), usage information (intended purpose (intended use), target group, area of application, operating conditions), safety information (warnings, precautions, contraindications), packaging information (sterility status, expiration date, lot number, storage conditions, notes on aseptic presentation), and regulatory information (manufacturer details, CE marking, symbols according to relevant standards). Which information is relevant in an individual case depends on the respective product and context of use.
Connection with use errors
Typical causes of labeling-related use errors are unclear wording, poorly understandable symbols, small font size, insufficient contrast, overloaded presentations of information, contradictory statements, warnings that are hard to find, or similar packaging designs for different product variants. In such cases the cause usually does not lie with the user but with an inadequate design of the information presentation, in line with the basic idea of human factors engineering to address risks at their cause rather than at the symptom.
Labeling and risk management
Within the use-related risk analysis, it is examined whether labeling is sufficiently visible, is interpreted correctly, is available at the right moment, and helps avoid potential use errors. The following applies: According to the basic principles of risk management, design solutions are generally preferred over warnings or training. Labeling and warnings should address risks in a supplementary way and not be the only risk control measure.
Labeling and packaging usability
Especially for medical device packaging, labeling forms an essential part of packaging usability. Users often have to recognize quickly where the packaging is opened, which side is sterile, which product or variant it contains, and how the product is to be removed. Good packaging usability therefore almost always also requires good labeling.
Connection with the instructions for use (IFU)
The instructions for use are a special component of labeling. While product labels and packaging mostly provide information for immediate use, the IFU often contains more detailed information on use, preparation, maintenance, warnings, and troubleshooting. Both elements should be designed consistently and complement each other rather than contradict each other.
Labeling is part of the user interface, not merely a mandatory regulatory document. Poorly designed labeling creates the same risks as a poorly designed operating interface.
Design solutions take precedence over warnings; labeling complements good product design but does not replace it.
Frequently asked questions (FAQ)
Is labeling only a mandatory regulatory document?
No. The FDA explicitly counts labeling as part of the user interface of a medical device. Labeling that is hard to find or misleading is therefore a usability problem, not a purely regulatory one, and is checked accordingly in usability studies.
Is an additional warning enough to address an identified risk?
As a rule, not if a design solution would be possible. According to the basic principles of risk management, design solutions take precedence over warnings and training, because labeling is, by experience, noticed less often than assumed under time pressure or in routine.
How are labeling and packaging usability related?
Very closely. Users must be able to recognize from the labeling quickly which product or variant is present, which side is sterile, and how to open it. A packaging that works in itself can still fail because of unclear labeling.
Do you want to know whether your labeling is actually found and correctly understood in a real-world situation? We test labeling as part of the entire user interface.
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