Ft4 Free Thyroxine: medical device reports filed with FDA

521 reports name it, 2011–2018. Manufacturer given most often on reports: Roche Diagnostics. Product code CEC.

Read first · FDA's statement on these data

Adverse event reports submitted to FDA do not undergo extensive validation or verification. Therefore, a causal relationship cannot be established between product and reactions listed in a report. While a suspected relationship may exist, it is not medically validated and should not be the sole source of information for clinical decision making or other assumptions about the safety or efficacy of a product. Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product. openFDA, FDA

FDA adds: "Although MDRs are a valuable source of information, this passive surveillance system has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data. In addition, the incidence or prevalence of an event cannot be determined from this reporting system alone due to potential under-reporting of events and lack of information about frequency of device use." And: "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices."

Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated.

Not medical advice. This site counts what was reported to FDA. Questions about a medicine or device belong with a pharmacist or clinician.

521
device reports naming the brand: 0% of all MAUDE reports · about 34 a year; 0
reports, 12 months to August 2026: 0 in the 12 months before; 100%
classified as malfunction: 98.4% across the product code; 0%
classified as death, as reported: 0 reports · not verified by FDA

FDA's MAUDE database holds 521 reports that name the brand "Ft4 Free Thyroxine" (radioimmunoassay free thyroxine), received between May 2011 and October 2018; the manufacturer given most often on reports is Roche Diagnostics. Spellings of one product vary from report to report.

0 reports arrived in the 12 months to August 2026, and none in the 12 months before. FDA releases MAUDE data monthly; reports can arrive months after an event, so the newest months grow in later releases. The event types recorded are malfunction (100%); across all radioimmunoassay, free thyroxine reports (product code CEC) death is recorded in 0% and malfunction in 98.4%. Event type is the reporter's classification of the report, not a verified outcome.

The device problems coded most often are high test results (61.8%), incorrect or inadequate test results (27.1%) and low test results (6.1%). FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data."

Reports by month, five years

No report naming Ft4 Free Thyroxine was received in the five years to August 2026; the latest was received in October 2018.

By year received

Event type and report source

Event type, as classified on the report

Death0%0

Injury0%0

Malfunction100%521

Other0%0

Not given0%0

Who filed the report

Manufacturer report100%521

Voluntary report0%0

User facility report0%0

Distributor report0%0

Not given0%0

Grey bar: all 1,934 reports carrying product code CEC. Event type is the filer's classification and is not verified by FDA.

Device problems coded

Device problem (FDA code)	Reports	Share	Share across product code
High test results	322	61.8%	69.5%
Incorrect or inadequate test results	141	27.1%	10.4%
Low test results	32	6.1%	10%
Incorrect, inadequate or imprecise result or readings	5	1%	4.8%
High readingsreadings were too high	2	0.4%	0.2%
Non reproducible results	2	0.4%	5.2%

FDA's device problem codes as entered on the report; one report can carry several. Generic codes such as "no apparent adverse event" are left out.

In context

Measure	Ft4 Free Thyroxine	Product code CEC	All MAUDE reports
Reports	521	1,934	26,136,888
Share of that pool	—	26.9%	0%
Classified as death, per 1,000 reports	0	0	9
Classified as injury	0%	1.3%	36.2%
Classified as malfunction	100%	98.4%	62.3%
Filed by the manufacturer	100%	99.8%	94.9%

Shares are of reports, not of devices in use. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data."

Other brands with product code CEC

Brand	Reports	Latest 12 months	Classified as death
Alinity I Free T4 Reagent Kit	374	125	0%
Dimension	1,139	40	0.1%

Ordered by report count for navigation only. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data." FDA also states that "common products may have a higher number of adverse events due to the higher total number of people using the product."

Questions about Ft4 Free Thyroxine reports

How many FDA reports name Ft4 Free Thyroxine?

521 medical device reports in the openFDA MAUDE release of 28 Sep 2026, covering reports received through August 2026; 0 in the latest 12 months.

What kinds of events are reported?

malfunction (100%). "Event type" is how the report was classified when filed: death, injury, malfunction or other.

What device problems are coded?

high test results (61.8%), incorrect or inadequate test results (27.1%), low test results (6.1%), incorrect, inadequate or imprecise result or readings (1%) and high readings (0.4%). These are FDA's device problem codes as entered on the report.

Who files these reports?

manufacturer reports (100%). Manufacturers and user facilities are required to report; voluntary reports come from health professionals and the public.

Do these reports show that Ft4 Free Thyroxine was at fault?

No. FDA states that "MDR data alone cannot be used to establish rates of events, evaluate a change in event rates over time or compare event rates between devices. The number of reports cannot be interpreted or used in isolation to reach conclusions about the existence, severity, or frequency of problems associated with devices." It adds that the reporting system "has limitations, including the potential submission of incomplete, inaccurate, untimely, unverified, or biased data." FDA adds that "a causal relationship cannot be established between product and reactions listed in a report."

How do I report a problem with a medical device?

Through FDA MedWatch (Form FDA 3500 for health professionals and consumers), or to the manufacturer. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Device Adverse Event (MAUDE) bulk export released 28 Sep 2026, which holds reports FDA received through 31 Aug 2026. Brand, generic and manufacturer names are as written on the reports; product code names come from FDA's device classification. A report counts here when any device it lists carries this brand name after punctuation and capitalisation are normalised. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.