(155 days)
The TP500 Infrared Thermometer is intended to measure human body temperature by measuring from 1-3cm distance to the forehead. The device can be used on people of all ages. It is recommended that the device be operated by an adult. The device is intended to be used in the hospital and other clinical environments.
The Infrared thermometer (model TP500) is a hand-held, battery powered, electronic thermometer that converts a subject's forehead temperature, using the infrared energy emitted in the area around the subject's forehead to an oral equivalent temperature when measured from 1-3cm to the center of the subject's forehead with no contact. The device can be used on people of all ages and is intended to be used in the hospital and other clinical environments.
Here's an analysis of the acceptance criteria and study that proves the device meets them, based on the provided FDA 510(k) summary for the Contec Medical Systems Co., Ltd. Infrared Thermometer (Model TP500).
This document is a 510(k) summary, which focuses on demonstrating substantial equivalence to a predicate device rather than providing a detailed report of all raw study data. Therefore, some information, especially regarding the specifics of how the ground truth was established for the training set, might not be fully elaborated.
1. Table of Acceptance Criteria and Reported Device Performance
The core performance of an infrared thermometer relates to its accuracy and repeatability. The primary standard for this, as cited, is ASTM E1965-98. The acceptance criteria are implicit in meeting this standard and are explicitly stated in the "Accuracy" row of the comparison table.
| Acceptance Criterion (Standard/Requirement) | Reference | Reported Device Performance (TP500) |
|---|---|---|
| Accuracy | ASTM E1965-98 / User Manual Claim | ±0.3°C (0.5°F) |
| Clinical Bias | ASTM E1965-98 | Evaluated and met performance parameters claimed |
| Clinical Uncertainty | ASTM E1965-98 | Evaluated and met performance parameters claimed |
| Clinical Repeatability | ASTM E1965-98 | Evaluated and met performance parameters claimed |
| Electrical Safety | IEC 60601-1 | Complies |
| Electromagnetic Compatibility (EMC) | IEC 60601-1-2 | Complies |
| Performance (General) | ISO 80601-2-56 | Complies |
| Biocompatibility | ISO 10993-5:2009 & ISO 10993-10:2010 | Complies (materials tested and shown not to affect effectiveness/safety) |
| Software Verification & Validation | FDA Guidance (May 11, 2005) | Met requirements |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: A "controlled human clinical study" was conducted with 108 subjects. These subjects included three age groups:
- Age 0-1 (35 subjects)
- Age 1-5 (33 subjects)
- Age above 5 (40 subjects)
- The study included both febrile and afebrile persons.
- Data Provenance: Not explicitly stated, but given the manufacturer is China-based, it is highly probable the data was collected in China. The study is described as a "controlled human clinical study," implying a prospective design for gathering the clinical accuracy data.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This detail is not provided in the summary. For a thermometer, the "ground truth" would typically be established by a highly accurate reference thermometer (e.g., a rectal thermometer or an oral thermometer operated by a trained healthcare professional, depending on the body site), rather than "experts" in the sense of multiple radiologists reviewing images. The summary states that "clinical bias, clinical uncertainty and clinical repeatability have been evaluated per clinical validation for infrared thermometer." This implies a comparison to a gold standard measurement, but the specifics of how many personnel were involved in taking these gold standard measurements or their specific qualifications are not detailed.
4. Adjudication Method for the Test Set
Adjudication methods (like 2+1, 3+1) are typically used for subjective assessments, such as image interpretation, to resolve discrepancies among experts. For objective measurements like temperature, an adjudication method is generally not applicable. Instead, the ground truth is established by a primary, highly accurate measurement method. The summary does not mention any adjudication process.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study was not done. MRMC studies are typically for medical imaging systems where human readers interpret images with and without AI assistance. This device is an infrared thermometer, not an imaging system designed for human interpretation with AI assistance. The study conducted was a clinical accuracy study comparing the device to a gold standard measurement, and implicitly, to the predicate device's performance per the equivalence claim.
6. If a Standalone (i.e., Algorithm Only Without Human-in-the-Loop Performance) Was Done
The device itself is a standalone thermometer. Its "performance" is inherently "algorithm only" in the sense that it provides a temperature reading directly. The clinical study evaluated the direct performance of the device's sensor and internal processing (algorithm) against a gold standard. So, yes, a standalone performance evaluation of the device's measurement capabilities was performed.
7. The Type of Ground Truth Used
The type of ground truth used was comparative measurements against a reference standard. The clinical study states that "clinical bias, clinical uncertainty and clinical repeatability have been evaluated per clinical validation for infrared thermometer." This means the device's readings were compared against highly accurate, established methods of temperature measurement to determine its accuracy and precision. While not explicitly stated as "rectal temperature" or "oral temperature," for a clinical thermometer, these are the typical gold standards depending on the population and clinical context. The study was conducted in accordance with ASTM E1965-98, which outlines the methodology for such clinical validations including the use of reference thermometers.
8. The Sample Size for the Training Set
Not applicable/Not explicitly stated for an AI training set. This device is a traditional medical device (infrared thermometer), not an AI/ML-based device that learns from a large training dataset in the same way, for example, a diagnostic imaging AI would. Its "algorithm" is based on physics (infrared radiation) and calibrated against known standards, not trained on patient data in an iterative machine learning process. Therefore, there is no "training set" in the context of machine learning.
9. How the Ground Truth for the Training Set Was Established
Not applicable. As explained in point 8, this is not an AI/ML device that requires a training set and associated ground truth in that context. The device's internal calibration and performance are established through engineering design, component selection, and adherence to performance standards like ISO 80601-2-56 and ASTM E1965-98, which involve physical calibrations, not data-driven machine learning training.
§ 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.