MedSun sits beside MAUDE, not inside it

Ask an RA operator where to check a device’s adverse-event history and the answer is MAUDE, almost by reflex. It is the right first answer. It is not the only database CDRH runs for this purpose, and the second one is built to catch precisely what MAUDE’s own reporting rule was never designed to reach.

A threshold, and what falls under it

21 CFR Part 803 sets the mandatory-reporting duty that eventually populates MAUDE: a manufacturer or user facility must report a device that may have caused or contributed to a death or serious injury, or that malfunctioned in a way that would be likely to cause or contribute to one if it recurred. That is a real, defined threshold, and crossing it is what makes a report reportable at all. Everything below that line — a device that behaved strangely but harmed no one, a workaround a nurse found before it mattered, a near-miss caught at the bedside — has no obligation attached to it and, absent something else, no reason to become a MAUDE record.

MedSun— the Medical Product Safety Network — is CDRH’s answer to that gap. Launched in 2002, it asks participating facilities a broader question than 803 does: not only what you were required to report, but what you noticed. FDA’s own description of the program is explicit that participants are encouraged to submit “close calls,” potential-for-harm events, and other safety concerns that never cross the mandatory line — the population 803 was never written to require in the first place.

A network, not a form

MedSun is not a wider MAUDE with a friendlier name. It is a defined, agreement-based network — roughly 300 hospitals, outpatient clinics, nursing homes, and home health agencies, per FDA’s own current estimate to the federal government’s information-collection reviewers — reporting directly to CDRH rather than through the manufacturer-mediated path most device MDRs travel. Reports live on their own legacy search tool at accessdata.fda.gov, carrying free-text Event Description and Manufacturer Narrative fields, and they are not part of openFDA. Query openFDA’s device-event endpoint — the one built on MAUDE — however you write it, and a MedSun-only report will never come back, because MedSun was never loaded into that endpoint to begin with.

MAUDE answers what a manufacturer or user facility was required to report. MedSun answers what someone at the bedside decided was worth mentioning anyway.

Where the signal actually surfaces

CDRH shares what the network turns up in a monthly MedSun newsletter, distributed to the clinical community with facility and patient identifiers stripped out. That channel has no CFR trigger, no compliance deadline, and no relationship to a recall number or a warning letter’s subject line — it can name a device problem pattern before anything else public does, and it can also name one that never becomes a recall, a warning letter, or even a MAUDE report at all.

The practice

Reading MedSun for your own device class is two separate habits, not an extension of reading MAUDE. The free-text search tool has to be queried directly, since no openFDA pipeline will surface it; the newsletter has to be read on its own cadence, since nothing about it resembles a database update. Neither one substitutes for MAUDE — roughly 300 facilities is a fraction of the several thousand that can generate a MAUDE report — and neither one is a finding about a specific device. A single close-call narrative from one facility is a data point a clinician chose to share, not a determination that anything is wrong with the product it names. This is regulatory intelligence and method, describing how two CDRH reporting channels differ and where each one is read, never a judgment about what any individual report means for any specific device.

Neither MAUDE nor MedSun sits inside FDA Radar’s current source coverage — per what we monitor and how often, the pipeline reads Federal Register notices, warning letters, recalls, and 510(k) clearances, none of which touches adverse-event data of either kind.