The indications for use describe, under 21 CFR 814.20(b)(3)(i), the disease or condition that a device diagnoses, treats, prevents, cures, or mitigates, including the patient population. At the FDA they are part of the broader intended use and are stated, for example, on the form FDA 3881.
Definition and legal basis
Indications for use (German: Indikationen) state what a medical device is intended to be used for in the US. The regulation 21 CFR 814.20(b)(3)(i), which governs the content of a PMA application (see PMA), describes them as a general description of the disease or condition that the device will diagnose, treat, prevent, cure, or mitigate, including a description of the patient population for which the device is intended. The requirement in 21 CFR 807.92(a)(5) for the 510(k) summary is almost identical, there as a statement of intended use. According to the FDA, it has long applied the definition of the PMA regulation in the 510(k) process as well (see 510(k) premarket notification).
In German, indications for use are usually rendered as indications (German: Indikationen). The MDR uses this term, for example in Annex I, Section 23.4 and Annex II, Section 1.1.
Intended use and indications for use
The FDA distinguishes the two terms. According to the guidance “The 510(k) Program: Evaluating Substantial Equivalence in Premarket Notifications [510(k)],” the intended use is the general purpose or function of the device and includes the indications for use. The indications for use are thus a part of it and specify the disease or condition and the patient population. The existing term Intended use treats the intended use in general terms; here the focus is on the FDA statement about it.
If the statement does not contain a disease, a condition, and a patient population, intended use and indications for use are the same. The guidance calls such statements “tool type,” for example a scalpel for cutting tissue or a device for imaging the body. A scalpel for a specific type of cancer cell, by contrast, does not have a tool-type indication.
The labeling is the source. Under Section 513(i)(1)(E) of the Federal Food, Drug, and Cosmetic Act (FD&C Act), the FDA determines the intended use in the 510(k) on the basis of the proposed labeling (see Labeling). The indications statement is also a factor. The guidance recommends keeping both consistent because this makes the review easier. In addition, the FDA can require that the labeling address a use that is not mentioned if that use is likely and could cause harm (“SE with limitations”). The general rule in 21 CFR 801.4 looks to the objective intent of the persons responsible for the labeling. It can also arise from advertising or statements by the manufacturer.
Where the indications for use are required
- 510(k): The form FDA 3881 “Indications for Use” contains the 510(k) number, if known, the device name, and a field for the indications. The applicant also selects the type of use: prescription use (21 CFR 801 Subpart D), over-the-counter use (21 CFR 801 Subpart C), or both. The statement can be continued on a second page (form version 8/23, to be checked for a newer version as of October 2026).
- 510(k) summary: Under 21 CFR 807.92(a)(5), it contains the intended use. If the indications differ from those of the predicate device, the summary must explain why the differences are not critical to the therapeutic, diagnostic, prosthetic, or surgical purpose and do not affect safety and effectiveness when the device is used as intended.
- Labeling: 21 CFR 807.87(e) requires that labels, labeling, and advertising adequately describe the device, its intended use, and the directions for use.
- PMA: The summary under 21 CFR 814.20(b)(3) begins with the indications for use.
Because substantial equivalence depends on the intended use, the indications also play a role in the choice of the predicate device (see Substantial equivalence and predicate device).
Changes to the indications
According to the guidance, not every change in the indications is a new intended use. This is only the case if it raises different questions of safety and effectiveness and therefore no longer allows a meaningful comparison with the predicate. According to the guidance, particular attention is required for:
- the change from a functional statement to a treatment or aesthetic indication,
- the change from diagnostics to screening or vice versa,
- a different anatomical structure,
- a different patient population, such as adults versus children,
- a different clinical setting, such as hospital versus home use or periodic versus continuous monitoring.
For a new or different indication, 21 CFR 807.87(g) requires evidence that the manufacturer has considered the consequences for safety and effectiveness. For an approved device, 21 CFR 814.39(a)(1) names new indications as a change for which a PMA supplement must be submitted if it affects safety or effectiveness.
Comparison with the MDR
Instead of the intended use, the MDR (the EU Medical Device Regulation) uses the intended purpose. Article 2(12) defines it as the use for which a device is intended according to the data supplied by the manufacturer on the label, in the instructions for use, in promotional or sales materials, and in the clinical evaluation (see MDR). Annex I, Section 23.4 requires the instructions for use to state the intended purpose with a precise specification of the indications, contraindications, target patient groups, and intended users. Annex II, Section 1.1 lists corresponding information for the technical documentation.
Both systems tie the term to statements by the manufacturer, and in both, the indications belong to the overall picture of the intended use. They cannot, however, be equated: The FDA guidance calls the indications a part of the intended use, whereas the MDR annexes list them alongside the intended purpose. Manufacturers active in both markets should therefore align wording and scope deliberately.
Significance for human factors
The FDA guidance “Content of Human Factors Information in Medical Device Marketing Submissions,” final since May 29, 2026, builds the flowchart for the HF categories on the indications for use and the use-related risk analysis (URRA) (see FDA human factors guidance). The indications thus determine how extensive the human factors evidence is.
- Descriptions: For categories 2 and 3, the guidance recommends a description of the intended user populations (see Intended user), a summary of the intended use, of the use environments with their characteristics such as glare, vibration, noise, or high activity (see Context of use), and of the training. The description of users, use, and environment is covered by the term Use specification.
- Changes: Decision point B of the guidance asks about changes in user interface, users, uses, use environments, training, or labeling. An extended indication can include such changes.
- Examples: The guidance addresses the extension of a glucose system to pediatric patients and of a controller to adults with type 2 diabetes. It treats this as a new intended user group. In the second example, no new critical tasks arise, but existing ones are affected because another user group performs them.
- Validation data: The FDA can also require data from human factors validation when they were not customary for the device type so far, for example in the case of new indications for use, a changed use environment, or new user groups.
It does not follow that every extension of the indications requires new validation data. The guidance reviews the individual case using its decision points. In practice, it is advisable to align the indications statement, the labeling, and the description of users and environments in the human factors report, and to reconcile changes to the indications with the URRA early.
According to 21 CFR 814.20(b)(3)(i), indications for use name the disease or condition that a device diagnoses, treats, prevents, cures, or mitigates, including the patient population. The FDA also applies this definition in the 510(k).
The intended use is the broader term and includes the indications for use. The FDA determines it in the 510(k) on the basis of the proposed labeling; the statement is made, among other places, on the form FDA 3881.
For human factors, the indications are the starting point of the HF categories. Changes in users, use, or environment can make new evidence necessary; the FDA guidance reviews this case by case.
Frequently asked questions (FAQ)
What is the difference between intended use and indications for use?
According to the FDA guidance on the 510(k), the intended use is the general purpose or function of a device and includes the indications for use. These specify the disease or condition and the patient population. If no such statements exist, for example for a scalpel for cutting tissue, the two terms are the same.
Where do I state the indications for use to the FDA?
For the 510(k), on the form FDA 3881 and, together with the intended use, in the 510(k) summary under 21 CFR 807.92. In addition, the labeling must adequately describe the device, its intended use, and its use. For a PMA application, the indications for use are at the beginning of the summary under 21 CFR 814.20(b)(3).
What happens if I want to extend the indication?
That depends on whether the change raises different questions of safety and effectiveness. For a 510(k), a new intended use can require a different pathway, such as PMA or De Novo. For an approved PMA device, a PMA supplement must be submitted for new indications that affect safety or effectiveness.
Does the MDR intended purpose correspond to the FDA intended use?
The terms are related but not identical. The MDR defines the intended purpose through statements on the label, in the instructions for use, in promotional material, and in the clinical evaluation, and lists the indications in the annexes alongside it. The FDA guidance understands the indications for use as part of the intended use.
Does an extended indication require new human factors data?
Not automatically. The FDA guidance on the content of human factors information examines whether users, uses, environment, training, labeling, or the user interface change and whether critical tasks are affected. A new user group can affect existing critical tasks; in that case the individual case must be assessed.
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More about our usability engineeringSources
- FDA Guidance: Content of Human Factors Information in Medical Device Marketing Submissions
- FDA Guidance: Applying Human Factors and Usability Engineering to Medical Devices
- Regulation (EU) 2017/745 on medical devices (MDR)
- 21 CFR 814.20, Application
- 21 CFR 807.87, Information required in a premarket notification submission
- 21 CFR 801.4, Meaning of intended uses
- 21 CFR 807.92, Content and format of a 510(k) summary
- 21 CFR Part 814, Premarket Approval of Medical Devices
- Federal Food, Drug, and Cosmetic Act, Section 513 (21 U.S.C. 360c), Classification of devices intended for human use
- FDA Guidance: The 510(k) Program: Evaluating Substantial Equivalence in Premarket Notifications [510(k)]