(126 days)
The wireless Fever Scout™ Continuous Monitoring thermometer is a non-invasive and re-usable electronic device for home use and a non-invasive and single patient use in the hospital. This product is intended for non-urgent ambulatory continuous armpit body temperature monitoring from ages 29 days and older.
The VivaLnk Fever Scout VV-200 is an ambulatory continuous body temperature monitor designed for armpit location, and uses Bluetooth Low Energy (BLE) for wireless communication with the Smartphone app for temperature display, trending and alert. The product is composed of The Fever Scout VV-200 patch, The Smartphone app (supporting Apple iOS and Android devices), AAA charging system with BLE relay function, Eight disposable adhesives.
The provided text describes the regulatory filing for a medical device, the Fever Scout Continuous Monitoring Thermometer (K181013), and its substantial equivalence to previously marketed predicate devices. The study detailed focuses on expanding the indications for use, particularly to include single-patient use in hospitals, rather than on proving new performance characteristics of the device itself.
Based on the information provided, here's a breakdown of the acceptance criteria and the study that proves the device meets them:
I. Acceptance Criteria and Reported Device Performance
The acceptance criteria for the Fever Scout™ Continuous Monitoring Thermometer are primarily based on its equivalence to existing predicate devices, particularly regarding its technical characteristics and compliance with recognized standards. Since the K181013 submission is for expanded indications for use (adding single-patient use in hospitals) for an identical product (VV-200) that was previously cleared (K162137), the performance acceptance criteria are implicitly those that the original predicate device met, and this submission seeks to demonstrate that the expanded use does not introduce new risks or alter its fundamental performance.
The table below summarizes the technical characteristics that serve as de facto "acceptance criteria" through comparison with predicates, along with the reported performance of the proposed device. The "Performance" section within the document refers to compliance with standards, indicating that meeting these standards serves as the primary proof of performance.
Table 1: Acceptance Criteria (Based on Predicate Equivalence) and Reported Device Performance
| Characteristic | Acceptance Criteria (based on Primary Predicate K162137 and Secondary K160306) | Reported Device Performance (K181013) |
|---|---|---|
| Measurement Range | 35 ~ 42°C (Primary Predicate); 25 ~ 45°C (Secondary Predicate) | 35 ~ 42°C |
| Accuracy | ±0.1°C From 37 ~ 39°C, ±0.2°C from 35 ~ 37°C and 39 ~ 42°C (Primary Predicate); ±0.1ºC (at 36.0 to 40.0°C), ±0.2ºC at other temp range (Secondary Predicate) | ±0.1°C From 37 ~ 39°C, ±0.2°C from 35 ~ 37°C and 39 ~ 42°C |
| Biocompatibility | Conformed to ISO 10993-1, ISO 10993-5, and ISO 10993-10 | Conformed to ISO 10993-1, ISO 10993-5, and ISO 10993-10 |
| Electrical Safety | Conformed to IEC 60601-1 | Conformed to IEC 60601-1 |
| Electromagnetic Compatibility | Conformed to IEC 60601-1 | Conformed to IEC 60601-1 |
| Performance (General) | Conformed to ASTM E1112 | Conformed to ASTM E1112 |
| Measurement Interval | Every 15 seconds (Primary Predicate); Every 4 seconds (Secondary Predicate) | Continuous transmitter measures body temperature every 15 seconds |
| Anatomical Application | Axillary (armpit) temperature measuring and monitoring | Axillary (armpit) temperature measuring and monitoring |
| Reuse | Re-usable for home use (Primary Predicate); Reusable for household and medical institutions (Secondary Predicate) | Re-usable for home use and single patient use in the hospital |
| Indications for Use | Non-urgent ambulatory continuous armpit body temperature monitoring from ages 29 days and older, for home use (Primary Predicate) and household/medical institutions (Secondary Predicate) | Non-urgent ambulatory continuous armpit body temperature monitoring from ages 29 days and older, for home use and single patient use in the hospital |
II. Study Details for Proving Acceptance Criteria
The document does not detail a new clinical study with a test set, expert readers, or ground truth establishment in the traditional sense of an AI model performance study. Instead, the proof of meeting acceptance criteria for this K181013 submission relies on:
- Demonstrating Substantial Equivalence: The primary method is to show that the proposed device (with expanded indications) is identical to a previously cleared predicate (K162137) for home use and comparable to a secondary predicate (K160306) for institutional use.
- Compliance with Recognized Consensus Standards: The document explicitly states that the device "Conformed to" or "Complied with" various international and ASTM standards (ISO 10993 series for biocompatibility, IEC 60601-1 for electrical safety and electromagnetic compatibility, and ASTM E1112 for performance of clinical thermometers). Adherence to these standards is considered sufficient evidence of safety and basic performance.
- Risk Management for Expanded Use: For the expanded "single patient use in the hospital," the submission addresses potential new risks (specifically cross-contamination) through a "Fever Scout Risk Management Report" and proposed procedural controls (labeling and IFU precautions). This is a mitigation strategy rather than a performance study.
Given this context, many of the requested details for a typical AI model study are not applicable or explicitly stated in this regulatory submission document.
- Sample size used for the test set and data provenance: Not explicitly detailed as a separate clinical test set for performance validation in this submission. The validation is through comparison to predicates and compliance with standards. If a test set was used for the original predicate's clearance (K162137) to meet ASTM E1112, those details are not provided here.
- Number of experts used to establish the ground truth for the test set and the qualifications of those experts: Not applicable. Ground truth for clinical thermometer performance is typically established through a known temperature reference (e.g., black body calibrators for laboratory accuracy tests, or controlled clinical studies comparing to a gold standard thermometer), as part of compliance with standards like ASTM E1112. The document doesn't describe the expert consensus process for a test dataset.
- Adjudication method (e.g., 2+1, 3+1, none) for the test set: Not applicable.
- If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance: Not applicable. This device is a thermometer, not an AI diagnostic tool primarily assisting human readers.
- If a standalone (i.e. algorithm only without human-in-the loop performance) was done: The device itself is "standalone" in continuously measuring temperature. Its performance is measured against established accuracy standards (ASTM E1112), not comparative human interpretation.
- The type of ground truth used (expert consensus, pathology, outcomes data, etc.): For thermometer performance, the ground truth is typically a highly accurate reference thermometer or a controlled temperature environment, as per standards like ASTM E1112. The document doesn't detail how ground truth was established for a specific "test set" in this submission.
- The sample size for the training set: Not applicable. This is not an AI model that undergoes a "training" phase with a dataset.
- How the ground truth for the training set was established: Not applicable.
In summary, the device's acceptance is based on its demonstrated substantial equivalence to predicate devices and its compliance with relevant performance and safety consensus standards, rather than a new, extensive clinical study detailing specific test sets, expert ground truth, or MRMC analyses. The expansion of indications for hospital use is addressed through a risk management approach for cross-contamination.
§ 880.2910 Clinical electronic thermometer.
(a)
Identification. A clinical electronic thermometer is a device used to measure the body temperature of a patient by means of a transducer coupled with an electronic signal amplification, conditioning, and display unit. The transducer may be in a detachable probe with or without a disposable cover.(b)
Classification. Class II (performance standards). The device is exempt from the premarket notification procedures in part 807, subpart E of this chapter, subject to the limitations in § 880.9 and the following conditions for exemption:(1) Device is not a clinical thermometer with telethermographic functions;
(2) Device is not a clinical thermometer with continuous temperature measurement functions; and
(3) Appropriate analysis and testing (such as that outlined in the currently FDA-recognized editions, as appropriate, of ISO 80601-2-56, “Medical electrical equipment—Part 2-56: Particular requirements for basic safety and essential performance of clinical thermometers for body temperature measurement,” or ASTM E1965, “Standard Specification for Infrared Thermometers for Intermittent Determination of Patient Temperature,” or ASTM E1112, “Standard Specification for Electronic Thermometer for Intermittent Determination of Patient Temperature,” or ASTM E1104, “Standard Specification for Clinical Thermometer Probe Covers and Sheaths”) must validate specifications and performance of the device.