Written and maintained by CASRAI Editorial Board
Last updated
General information about a public FDA database, not medical advice and not a safety verdict on any device.
Short answer
A MAUDE report is one medical device report (MDR) in FDA’s Manufacturer and User Facility Device Experience database: a manufacturer, importer, user facility or voluntary reporter describing a death, serious injury or malfunction involving a device. Read four things first: the report number, the event type, the narrative and the problem codes. Treat each record as an unverified account, not as proof that the device caused the event.
What a MAUDE report is
FDA describes MAUDE as a database of medical device reports of adverse events. The reporters are manufacturers, importers, user facilities and voluntary reporters. MDRs are one of several sources FDA uses for postmarket surveillance, alongside other tools. For the mandatory reporting rules behind the records, see the medical device reporting (MDR) term; for the form that mandatory reporters file, see the MedWatch Form 3500A walk-through. Drug reports live in a different system, covered under FAERS.
FDA’s own caution is that submitting an MDR does not necessarily show the device caused or contributed to the outcome. It also states that the data is not intended to be used to evaluate rates of adverse events, and names under-reporting, inaccuracies in reports and the lack of verification that the device caused the event as reasons.
How to read one record, field by field
FDA’s MAUDE page names the fields below. The openFDA device adverse event API exposes the same information under machine-readable names, which is useful if you move between the web search and downloaded data.
| FDA MAUDE field | openFDA field | What to look for |
|---|---|---|
| Report Number | report_number | For mandatory reporters it encodes the submitter ID, the year and a sequence number. Voluntary reports begin with "MW". |
| Type of Reportable Event | event_type | Death, serious injury or malfunction (the three categories FDA lists). |
| Event or Problem Description | mdr_text (text type "Description of Event or Problem") | The narrative, written by the reporter. This is where the circumstances are. |
| Medical Device Problem Code | product_problems | Codes meant to describe the device failure or problem most accurately; in the API they appear as plain-language problem terms. |
About the problem codes
FDA’s guidance on coding MDRs tells mandatory reporters to select the lowest-level, most detailed code that describes the event. Because the codes are hierarchical, a parent code already covers its child codes, so a reporter needs only the child. A problem code therefore tells you how the reporter classified the failure, at the detail level the reporter chose, and it is not an independent finding.
A reading checklist
- Check the report number. An "MW" prefix marks a voluntary report; other numbers come from mandatory reporters.
- Read the narrative, not just the event type. A JAMA Internal Medicine study found that the label can understate what the text describes (see the next section).
- Treat the problem code as the reporter’s classification. It is a coding choice, not a verified root cause.
- Do not turn counts into rates. FDA says the data is not intended for evaluating rates of adverse events, and openFDA says incidence or prevalence cannot be determined from this reporting system alone.
- Note the date received and the source. openFDA records carry a date_received and a report source (for example, a manufacturer report), which tell you who filed it and when.
- Pair it with other evidence. openFDA says the reports should not be the sole source of information for clinical decision making.
MAUDE web search, MDR data files and openFDA
The same underlying reports can be reached three ways.
| Route | What the source says |
|---|---|
| FDA MAUDE web search | Contains the last ten years of MDR data; updated every month with reports received through the last day of the previous month. |
| MDR data files | Downloadable zipped data files, updated monthly; they include voluntary reports since June 1993 and user facility reports since 1991. |
| openFDA device adverse event API | Page states the data is updated weekly. Not all MDRs provide UDI data, and the current data is not validated. |
The practical consequence is that the same question can return different coverage depending on the route: the web search looks back ten years, while the data files reach back further. A plain-text search for a device name is only as good as the names reporters typed; product codes are a steadier way to group devices, as explained in the FDA product classification database guide.
Where it matters for labs, clinics and supply decisions
Staff who evaluate equipment and consumables sometimes check MAUDE alongside FDA clearance data. The FDA 510(k) data guide covers how MAUDE sits next to the premarket databases, and what counts as a medical device explains which products fall under these reporting rules at all. FDA’s position is that MDRs are one of several surveillance sources, so a MAUDE search is a lead to follow up, for instance by reading the manufacturer’s own notices, and not a ranking of products. This page does not assess any specific device.
Common misunderstandings
"A report in MAUDE means the device failed."
Not necessarily. FDA says an MDR does not necessarily demonstrate that the device caused or contributed to the adverse outcome, and openFDA says a causal relationship cannot be established from a report.
"More reports means a worse device."
FDA states the data is not intended to evaluate rates. Report counts depend on how many devices are in use and on how much reporting happens, and FDA itself notes under-reporting.
"The event type is the final word."
A 2021 JAMA Internal Medicine study (Lalani and colleagues) searched MAUDE from 1991 to April 2020 with 70 death-related terms. Of 290,141 serious injury or death reports, 151,145 (52.1%) were classified as death. In a random sample of 1,000 of the 138,996 reports not classified as death, about 23% described a death but were filed under malfunction, injury, other or missing. That is a finding about those reports in that period; it is why the narrative deserves a read.
FAQ
What is the MAUDE adverse event report?
It is a medical device report stored in FDA’s MAUDE database, filed by a manufacturer, importer, user facility or voluntary reporter to describe a death, serious injury or malfunction involving a device.
How does MAUDE search work?
FDA provides a web search over the last ten years of MDR data, refreshed monthly. Older reports are in the downloadable MDR data files, and openFDA offers an API that its page says is updated weekly.
Is the MDR database the same as MAUDE?
MAUDE is the FDA database that holds MDRs. People also say "FDA MDR database" for the same collection, or for the downloadable MDR data files, which are the same reports in file form.
Can I use MAUDE to compare device safety?
Not on its own. FDA states the data is not intended to evaluate adverse event rates and that a report does not necessarily show the device caused the outcome.
Sources
- FDA, About the Manufacturer and User Facility Device Experience (MAUDE) Database, checked 2026-11-01.
- FDA, How to Code an MDR Adverse Event Report, checked 2026-11-01.
- openFDA, Device adverse event API, checked 2026-11-01.
- Lalani C, Kunwar EM, Kinard M, Dhruva SS, Redberg RF. Reporting of Death in US Food and Drug Administration Medical Device Adverse Event Reports in Categories Other Than Death. JAMA Internal Medicine, 2021. PMC8314174, checked 2026-11-01.
