Positive Predictive Value (PPV) of 98.2% (97.5% LCB: 96.4%)
—
—
Clinical study of 225 subjects who received a positive algorithm detection while wearing an ECG patch.
>1 (medical professionals)
Indications for Use
The Fitbit Irregular Rhythm Notifications feature is a medical device (SaMD). The Fitbit Irregular Rhythm Notifications feature analyzes pulse rate data to identify heart rhythms that are consistent with atrial fibrillation (AFib) and if identified, provide a notification to the user.
Device Story
Software-only mobile medical application (SaMD) analyzing pulse rate data from compatible consumer wrist-worn PPG sensors (smartwatches/fitness trackers). PPG sensors use LEDs/photodiodes to detect blood flow fluctuations; device measures beat-to-beat intervals during user stillness/sleep. Algorithm classifies tachograms as AFib-suggestive, no signs of AFib, or unanalyzable. Notifications surfaced to user via Fitbit mobile app (UI/display) once per 24-hour period. Used by laypeople for opportunistic AFib screening; supplements clinical decision-making. Does not replace traditional diagnosis/treatment. Benefits include early detection of potential AFib in asymptomatic users.
Clinical Evidence
Clinical study evaluated algorithm performance in 225 subjects who received a positive detection while wearing a concurrent ECG patch. Primary endpoint was Positive Predictive Value (PPV), which was 98.2% (97.5% LCB: 96.4%). No adverse events were related to the software; reported events were related to skin irritation from wearables or study participation. Bench testing verified signal acquisition, aggressor conditions, and algorithm classification accuracy.
Technological Characteristics
SaMD; algorithm classifies PPG-derived pulse rate data. Compatible with consumer wrist-worn PPG sensors (LED/photodiode). Mobile app UI for onboarding, education, and notification display. Software level of concern: moderate. Data stored locally on wearable before server transmission. No specific material standards cited for hardware; software-based analysis.
Indications for Use
Indicated for adults 22+ years old without prior AFib diagnosis to analyze pulse rate data from compatible wrist-worn devices to identify irregular rhythms suggestive of AFib. Intended for OTC use. Not for continuous monitoring; not for use in individuals previously diagnosed with AFib.
Regulatory Classification
Identification
A photoplethysmograph analysis software device for over-the-counter use analyzes photoplethysmograph data and provides information for identifying irregular heart rhythms. This device is not intended to provide a diagnosis.
Special Controls
In combination with the general controls of the FD&C Act, the photoplethysmograph analysis software for over-the-counter use is subject to the following special controls:
- 1. Clinical performance testing must demonstrate the performance characteristics of the detection algorithm under anticipated conditions of use.
- 2. Software verification, validation, and hazard analysis must be performed. Documentation must include a characterization of the technical specifications of the software, including the detection algorithm and its inputs and outputs.
- 3. Non-clinical performance testing must demonstrate the ability of the device to detect adequate PPG signal quality.
- 4. Human factors and usability testing must demonstrate the following:
- The user can correctly use the device based solely on reading the device labeling; a. and
- b. The user can correctly interpret the device output and understand when to seek medical care.
- 5. Labeling must include:
- a. Hardware platform and operating system requirements;
- b. Situations in which the device may not operate at an expected performance level;
- A summary of the clinical performance testing conducted with the device: C.
- d. A description of what the device measures and outputs to the user; and
- Guidance on interpretation of any results. e.
In combination with the general controls of the FD&C Act, the hardware and software for optical camera-based measurement of pulse rate, heart rate, breathing rate and/or respiratory rate is subject to the following special controls:
*Classification.* Class II (special controls). The special controls for this device are:(1) Clinical performance testing must demonstrate the performance characteristics of the detection algorithm under anticipated conditions of use.
(2) Software verification, validation, and hazard analysis must be performed. Documentation must include a characterization of the technical specifications of the software, including the detection algorithm and its inputs and outputs.
(3) Non-clinical performance testing must demonstrate the ability of the device to detect adequate photoplethysmograph signal quality.
(4) Human factors and usability testing must demonstrate the following:
(i) The user can correctly use the device based solely on reading the device labeling; and
(ii) The user can correctly interpret the device output and understand when to seek medical care.
(5) Labeling must include:
(i) Hardware platform and operating system requirements;
(ii) Situations in which the device may not operate at an expected performance level;
(iii) A summary of the clinical performance testing conducted with the device;
(iv) A description of what the device measures and outputs to the user; and
(v) Guidance on interpretation of any results.
Predicate Devices
Apple Inc., Irregular Rhythm Notification Feature (DEN180042)
Submission Summary (Full Text)
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April 8, 2022
Fitbit Inc Randy Parry Senior Regulatory Affairs Specialist 199 Fremont Street 14th Floor San Francisco, California 94105
Re: K212372
Trade/Device Name: Fitbit Irregular Rhythm Notifications Regulation Number: 21 CFR 870.2790 Regulation Name: Photoplethysmograph Analysis Software For Over-The-Counter Use Regulatory Class: Class II Product Code: QDB Dated: March 8, 2022 Received: March 9, 2022
Dear Randy Parry:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's
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requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Jennifer Shih Kozen Assistant Director Division of Cardiac Electrophysiology, Diagnostics and Monitoring Devices Office of Cardiovascular Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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## DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Indications for Use
510(k) Number (if known) K212372
Device Name
### Fitbit Irreqular Rhythm Notifications
Indications for Use (Describe)
The Fitbit Irregular Rhythm Notifications is a software-only mobile medical application that is intended to be used with compatible consumer wrist-worn products to analyze pulse rate data to identify episodes of irregular heart rhythms suggestive of atrial fibillation (AFib) and provide a notification to the user.
The Fitbit Irregular Rhythm Notifications is intended for over-the-counter (OTC) use. It is not intended to provide a notification on every episode of irregular rhythm suggestive of AFib and the absence of a notification is not intended to indicate no disease process is present; rather the Fitbit Irregular Rhythm Notifications is intended to opportunistically surface a notification of possible AFib when sufficient data are available for analysis.
These data are only captured when the user's still. Along with the user's risk factors, the Fitbit irreqular Rhythm Notifications can be used to supplement the decision for AFib screening. The Fitbit Irregular Rhythm Notfications is not intended to replace traditional methods of diagnosis or treatment.
The Fitbit Irregular Rhythm Notifications has not been tested for use in people under 22 years of age. It is also not intended for use in individuals previously diagnosed with AFib.
Type of Use (Select one or both, as applicable)
□ Prescription Use (Part 21 CFR 801 Subpart D)
X Over-The-Counter Use (21 CFR 801 Subpart C)
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Image /page/3/Picture/0 description: The image shows the Fitbit logo. The logo consists of a stylized turquoise-colored icon made up of small circles arranged in a pattern resembling a stylized person, followed by the word "fitbit" in a dark blue sans-serif font. The icon is positioned to the left of the word "fitbit".
#### 510(K) Summary VII.
#### 1. Submitter Information: Fitbit LLC 199 Fremont Street, 14th Floor
San Francisco, CA 94105
Contact Person: Randy Parry Phone: (415) 985-4778 Email: parran@google.com Date Prepared: March 8, 2022
#### 2. Subject Device Information
Name of Device: Fitbit Irregular Rhythm Notifications Common or Usual Name: Irregular Rhythm Analysis Software Classification Name: Photoplethysmograph Analysis Software For Over-The-Counter Use Regulatory Class: Class II Product Code: QDB - 21 CFR 870.2790
- 3. Predicate Device Apple Inc., Irregular Rhythm Notification Feature (DEN180042)
#### 4. Indications for Use
The Fitbit Irregular Rhythm Notifications is a software-only mobile medical application that is intended to be used with compatible consumer wrist-worn products to analyze pulse rate data to identify episodes of irregular heart rhythms suggestive of atrial fibrillation (AFib) and provide a notification to the user.
The Fitbit Irreqular Rhythm Notifications is intended for over-the-counter (OTC) use. It is not intended to provide a notification on every episode of irregular rhythm suggestive of AFib and the absence of a notification is not intended to indicate no disease process is present; rather the Fitbit Irregular Rhythm Notifications is intended to opportunistically surface a notification of possible AFib when sufficient data are available for analysis.
These data are only captured when the user is still. Along with the user's risk factors, the Fitbit Irreqular Rhythm Notifications can be used to supplement the decision for AFib screening. The Fitbit Irreqular Rhythm Notifications is not intended to replace traditional methods of diagnosis or treatment.
The Fitbit Irregular Rhythm Notifications has not been tested for and is not intended for use in people under 22 years of age. It is also not intended for use in individuals previously diaqnosed with AFib.
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Image /page/4/Picture/0 description: The image shows the Fitbit logo. The logo consists of a stylized, teal-colored geometric shape to the left of the word "fitbit" in a dark teal sans-serif font. The geometric shape is made up of several small circles arranged in a grid-like pattern.
#### 5. Device Description
## Intended Use
The Fitbit Irregular Rhythm Notifications feature is a medical device (SaMD). The Fitbit Irregular Rhythm Notifications feature analyzes pulse rate data to identify heart rhythms that are consistent with atrial fibrillation (AFib) and if identified, provide a notification to the user.
# Technological Characteristics
The Fitbit Irreqular Rhythm Notifications consists of an algorithm that classifies pulse rate data, and a mobile application run within the Fitbit app that serves as the user interface (UI) and device display.
The Fitbit Irregular Rhythm Notifications leverages pulse rate data collected from compatible commercially available, general purpose wrist-worn products (e.g., smartwatch or fithess tracker). Photoplethysmograph (PPG) sensors consist of light-emitting diodes (LED) and photodiodes that detect changes in blood flow of a user's vasculature at any given moment. When the heart beats, it sends a pressure wave through the vasculature causing a blood flow increase. By monitoring the fluctuations the consumer wrist-worn products can measure pulse rate data. When the user is still the sensor detects when individual pulses reach the periphery (i.e., wrist) and measures beat-to-beat intervals.
If the analyzed data are consistent with signs of atrial fibrillation, a notification indicating that a heart rhythm showing signs suggestive of AFib will be displayed to the user. The Fitbit Irregular Rhythm Notifications will only surface a notification of a heart rhythm showing signs of AFib once in a 24-hour period.
The Fitbit Irregular Rhythm Notifications mobile app functions within the Fitbit consumer application and is run on a compatible, user-provided general purpose mobile computing product (e.g., smartphone or tablet). The Fitbit Irregular Rhythm Notifications mobile app serves as the display/user interface for the Fitbit Irregular Rhythm Notifications.
| Table 7.1 Summary of Technological Characteristics and Substantial Equivalence | | |
|--------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| | Subject Device<br>Fitbit Irregular Rhythm Notifications | Predicate Device<br>Apple - Irregular Rhythm Notification |
| Intended Use | Analyze pulse rate gathered from<br>PPG pulse rate data to identify<br>episodes of irregular heart rhythms<br>suggestive of atrial fibrillation (AFib)<br>and provide a notification to the user. | Analyze pulse rate gathered from<br>PPG pulse rate data to identify<br>episodes of irregular heart rhythms<br>suggestive of atrial fibrillation (AFib)<br>and provide a notification to the user. |
| Indications for Use | The Fitbit Irregular Rhythm Notifications<br>is a software-only mobile medical<br>application that is intended to be used<br>with compatible consumer wrist-worn<br>products to analyze pulse rate data to<br>identify episodes of irregular heart<br>rhythms suggestive of atrial fibrillation<br>(AFib) and provide a notification to the<br>user.<br>The Fitbit Irregular Rhythm Notifications<br>is intended for over-the-counter (OTC)<br>use. It is not intended to provide a<br>notification on every episode of irregular<br>rhythm suggestive of AFib and the<br>absence of a notification is not intended<br>to indicate no disease process is<br>present; rather the Fitbit Irregular<br>Rhythm Notifications is intended to<br>opportunistically surface a notification of<br>possible AFib when sufficient data are<br>available for analysis.<br>These data are only captured when the<br>user is still. Along with the user's risk<br>factors, the Fitbit Irregular Rhythm<br>Notifications can be used to supplement<br>the decision for AFib screening. The<br>Fitbit Irregular Rhythm Notifications is<br>not intended to replace traditional<br>methods of diagnosis or treatment.<br>The Fitbit Irregular Rhythm Notifications<br>has not been tested for and is not<br>intended for use in people under 22<br>years of age. It is also not intended for<br>use in individuals previously diagnosed<br>with AFib. | The Irregular Rhythm Notification<br>Feature is a software-only mobile<br>medical application that is intended to<br>be used with the Apple Watch. The<br>feature analyzes pulse rate data to<br>identify episodes of irregular heart<br>rhythms suggestive of atrial fibrillation<br>(AFib) and provides a notification to the<br>user.<br>The feature is intended for<br>over-the-counter (OTC) use. It is not<br>intended to provide a notification on<br>every episode of irregular rhythm<br>suggestive of AFib and the absence of a<br>notification is not intended to indicate no<br>disease process is present; rather the<br>feature is intended to opportunistically<br>surface a notification of possible AFib<br>when sufficient data are available for<br>analysis.<br>These data are only captured when the<br>user is still. Along with the user's risk<br>factors, the feature can be used to<br>supplement the decision for AFib<br>screening. The feature is not intended to<br>replace traditional methods of diagnosis<br>or treatment.<br>The feature has not been tested for and<br>is not intended for use in people under<br>22 years of age. It is also not intended<br>for use in individuals previously<br>diagnosed with AFib. |
| Mechanism of<br>Operation | Software-only mobile medical application<br>that uses inputs from compatible<br>consumer wrist-worn PPG sensors to<br>analyze pulse rate data to identify<br>episodes of irregular heart rhythms<br>suggestive of AFib. | Software-only mobile medical<br>application that uses inputs from<br>wrist-worn Apple Watch PPG sensors to<br>analyze pulse rate data to identify<br>episodes of irregular heart rhythms<br>suggestive of AFib. |
| Device<br>Classification | Class II | Class II |
| | | |
| FDA Product Code<br>and Regulatory<br>Classification | QDB - 870.2790 | QDB - 870.2790 |
| | Photoplethysmograph analysis software<br>for over-the-counter use | Photoplethysmograph analysis software<br>for over-the-counter use |
| Anatomical Site | Wrist-worn compatible consumer<br>product with PPG sensors. | Wrist-worn Apple Watch with PPG<br>Sensors |
| Patient Population | Individuals (22 years or older) | Individuals (22 years or older) |
| Data storage | Pulse rate data stored locally on<br>wrist-worn product until transmission to a<br>server. | Pulse rate data stored locally on<br>wrist-worn product until transmission to<br>a server. |
| Prescription/OTC | OTC | OTC |
| User interface | Mobile application run within the Fitbit<br>consumer app. | Mobile application run within the iPhone<br>Apple Health App. |
| Use Method | Collects and analyzes tachograms<br>during periods of stillness or sleep using<br>input from PPG sensors. | Collects and analyzes a one-minute<br>tachogram approximately every 4 hours<br>using input from PPG sensors. |
| Limiting Factors | Motion, hand and finger movements,<br>dark tattoos on the wrist, inadequate<br>blood flow.<br>Does not continuously monitor for signs<br>of AFib.<br>A lack of notification does not indicate an<br>absence of AFib. | Motion, hand and finger movements,<br>dark tattoos on the wrist, inadequate<br>blood flow.<br>Does not continuously monitor for signs<br>of AFib.<br>A lack of notification does not indicate<br>an absence of AFib. |
| Results of<br>algorithm | Tachograms are classified as having<br>signs of AFib, no signs of AFib or<br>unanalyzable. | Tachograms are classified as either<br>irregular rhythm or not AFib.<br>Notification of a heart rate that shows<br>signs consistent with atrial fibrillation. |
| History of events | History of events consistent with AFib<br>viewable in the mobile application. | History of events consistent with AFib<br>viewable in the mobile application. |
| Compatible<br>devices | Consumer wrist-worn products with PPG<br>sensors (e.g., smartwatch or fitness<br>tracker) that have been qualified for use<br>with Fitbit Irregular Heart Rhythm<br>Notifications<br>Fitbit Sense<br>Fitbit Versa<br>Fitbit Versa Lite<br>Fitbit Inspire 2 | Apple Watch with PPG sensors (series 1<br>and later). |
| Fitbit Charge 4 | | |
| | | |
## Summary of Technological Characteristics and Substantial Equivalence
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Image /page/5/Picture/0 description: The image shows the Fitbit logo. The logo consists of a teal-colored icon made up of several circles arranged in a diamond shape, followed by the word "fitbit" in a sans-serif font, also in teal. The logo is simple and modern, reflecting the company's focus on health and fitness tracking.
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Image /page/6/Picture/0 description: The image shows the Fitbit logo. The logo consists of a stylized turquoise icon made up of several circles arranged in a geometric pattern, followed by the word "fitbit" in a dark blue sans-serif font. The icon is positioned to the left of the word "fitbit".
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#### 6. Performance Data
Testing verifying the performance requirements of the subject device was conducted and is included in this premarket notification, the results of which support substantial equivalence. A summary of the testing is included below:
# Bench Testing/Non-Clinical Testing
The Fitbit Irreqular Rhythm Notifications utilizes signals derived from compatible consumer grade wrist-worn products. The wrist-worn products are qualified for use with the software to ensure that the data provided meet signal attribute and quality requirements necessary for heart rhythm analysis and to detect adequate PPG signal quality. Bench testing includes: product signal acquisition testing, aggressor testing for known challenge conditions potentially impacting the quality of PPG signal acquisition, and accuracy assessment of the inputs to the Fitbit Irregular Rhythm Notifications that are derived from the wrist-worn products. Qualification testing is repeated for all qualified wrist-wearable products. The algorithm is tested to ensure that it accepts and rejects data correctly and that it correctly analyzes the input data.
# Software Testing Summary
The Fitbit Irregular Rhythm Notifications presents a "moderate" level of concern (LOC) as defined in FDA's Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices (May 11, 2005) (Guidance Document). The software components consist of the Irregular Rhythm Notifications algorithm, which resides/runs on Fitbit servers, and the mobile app used for on-boarding, education and display of notification results. Testing supports that the algorithm analyzes pulse rate data and classifies it as having signs of AFib, having no signs of AFib, or unanalyzable. Testing of the mobile application demonstrates that the Fitbit Irregular Rhythm Notifications mobile application adequately surfaces on-boarding/educational information, generates user notifications when the feature identifies an irregular rhythm suggestive of AFib, and facilitates viewing of that notification.
# Human Factors Testing Summary
A human factors study was designed to evaluate the critical and noncritical tasks associated with the use of the device.
Human Factors Usability testing was performed using a simulated version of the Fitbit Irregular Rhythm Notifications mobile app, representative of the final app. There were a total of 30 subjects distributed into two (2) user groups:
- 15 active interest participants adult laypeople (22 years and older) with active . interest in AFib, defined as individuals who:
- o Have concern regarding AFib and have an active interest in monitoring potential AFib, and
Confidential
## K212372 Page 5 of 7
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Image /page/8/Picture/0 description: The image shows the Fitbit logo. The logo consists of a stylized, teal-colored icon to the left of the word "fitbit" in a sans-serif font, also in teal. The icon is made up of a grid of small circles arranged in a diamond shape.
- Would use the app due to high interest o
- 15 passive interest participants adult laypeople (22 years and older) with passive ● interest in AFib, defined as individuals who:
- Do not have concern regarding AFib and do not have an active interest in O monitoring potential AFib. and
- Might use the app due to casual or passing interest. o
The Human Factors Validation demonstrated that the Fitbit Irregular Rhythm Notifications meets the special control requirements for human factors and usability testing that demonstrates the following:
a. The user can correctly use the device based solely on reading the device labeling.
b. The user can correctly interpret the device output and understand when to seek medical care.
Testing was also performed to assess consumers' ability to correctly self-select if the Irregular Rhythm Notifications app is intended for them. This testing involved 33 subjects, including both users for whom the app is intended, as well as persons outside the app's intended use population. The testing concluded that users can adequately self-select if the device is intended for them.
# Clinical Testing Summary
A clinical study was conducted on the Fitbit Irreqular Rhythm Notifications algorithm. This study recruited subjects from Fitbit's U.S. user population, inviting them to participate in a study. Upon consent, users had their PPG data analyzed for signs consistent with AFib by the algorithm. The users whose data showed signs of AFib were then instructed to schedule a telehealth visit with a clinician. Subjects still meeting the inclusion criteria were then provided with an ECG patch and directed to simultaneously wear both the ECG patch and their Fitbit wrist-wearable, PPG-equipped product for seven (7) consecutive days and nights. Data gathered from the ECG patch was analyzed by medical professionals to determine whether signs of AFib were present and was compared to the corresponding Fitbit algorithm output.
In the 225 subjects who received a positive algorithm detection while wearing the ECG patch, the algorithm's positive predictive value (PPV) was 98.2% (97.5% LCB: 96.4%) and supports that the subject Fitbit Irreqular Rhythm Notifications is substantially equivalent to the predicate, Apple Inc. Irregular Rhythm Notification. A total of 2,094 adverse events were reported for 1,275 subjects. No adverse events reported were related to the Fitbit Irregular Rhythm Notifications software. Most adverse events were identified as possible risks in the study protocol, namely skin irritation from wearing a Fitbit or ECG patch, stress or anxiety from participating in the study, new information or diagnosis as the result of being in the study and combinations of multiple events.
#### 7. Conclusion
The Fitbit Irregular Heart Rhythm Notifications is as safe and effective as the Apple -Irregular Rhythm Notification. Additionally, minor technological differences between the Fitbit
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Image /page/9/Picture/0 description: The image shows the Fitbit logo. The logo consists of a stylized, teal-colored icon to the left of the word "fitbit" in a dark teal sans-serif font. The icon is made up of a grid of circles, with the circles varying in size.
feature and its predicate do not raise different questions of safety or effectiveness compared to the predicate. The Fitbit Irregular Heart Rhythm Notifications has the same intended use, indications for use, underlying technological characteristics, and similar principles of operation as the predicate device. Based on the similarities and performance testing, the subject device, Fitbit Irregular Rhythm Notifications, is substantially equivalent to the predicate device.
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Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.