(86 days)
The Actiwatch-Score® is a compact, lightweight, wrist-worn activity monitor that can be used to analyze circadian rhythms, automatically collect and analyze data for sleep parameters, and assess activity in any instance where quantifiable analysis of physical motion is desirable. In addition, the Actiwatch-Score® has a built-in score pad that allows the subject to subjectively assign and enter a score from 0 to 9. The score pad can be used as a substitute or in addition to the traditional patient diary used in conjunction with activity monitoring.
The Actiwatch-Score® is a compact, wrist-worn, battery-operated activity monitor whose physical characteristics are similar to a small wristwatch. The monitor consists of the activity monitor itself and a disposable wrist band. The Actiwatch-Score® is intended for the measurement, storage, and analysis of body activity. The Actiwatch-Score® can be attached to the subject's limb and through the use of an accelerometer, motion of that limb is measured, the activity stored within the activity monitor. A computer program is used to set up the Actiwatch-Score® to collect data. This program is called Actiware-Sleep and runs on an IBM-compatible personal computer (PC). The major functions of Actiware-Sleep are to create a patient score schedule, program the device to collect data, retrieve the data from the activity monitor, display the data, and to store the data for future reference and comparison. The Actiwatch® Reader is a compact interface device that provides a communications link between the Actiwatch-Score® and the PC. The Actiwatch® Reader is connected to the serial communications port of the PC via a standard 9-conductor RS-232 cable. The Actiwatch-Score® utilizes a motion sensor known as an "accelerometer" to monitor the occurrence and degree of motion. This type of sensor integrates the amplitude and speed of motion and produces a small signal whose magnitude and duration depend on the amount of motion. The activity signals are amplified and digitized by the on-board circuit. This information is stored in memory on board the device as activity counts. In addition, the patient self-score data are stored as integer values within memory.
Acceptance Criteria and Study for Actiwatch-Score®
Here's an analysis of the provided text regarding the acceptance criteria and supporting studies for the Actiwatch-Score® device:
1. Table of Acceptance Criteria and Reported Device Performance:
The document describes two key performance aspects for the Actiwatch-Score® related to its new "score" feature:
| Parameter | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Audible Signal Timing | 100% timing agreement with a standard chronograph for alerting the patient to enter a score. | Tested using a schedule where the device alerted every 15 minutes. The Actiwatch-Score® audible alarm was in 100% timing agreement with the chronograph standard. (Pass) |
| Patient Score Recording Accuracy | No errors or disagreement between entered scores and recorded scores. | Tested by programming the device to beep hourly from 12:00 noon to 21:00. A score was entered for each beep. Data was downloaded, and recorded scores were compared to entered scores. No errors nor disagreement were noted between the entered scores and the recorded scores. (Pass) |
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size:
- Audible Signal Timing: "a device" (singular) was used.
- Patient Score Recording Accuracy: "An Actiwatch-score" (singular) was used.
- Data Provenance: The studies appear to be prospective internal validation tests conducted by the manufacturer, Mini-Mitter Co., Inc. The country of origin is implicitly the USA, where Mini-Mitter Co., Inc. is located.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
- No external experts are mentioned for establishing ground truth for these specific tests.
- For the audible signal timing test, the ground truth was established by a chronograph standard.
- For the patient score recording accuracy test, the ground truth was the manually entered scores by a tester.
4. Adjudication Method for the Test Set:
- None explicitly stated or implied. The tests relied on direct comparison to a timing standard (chronograph) or the known input of a score.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done:
- No, an MRMC comparative effectiveness study was not done. The document focuses on the technical functionality of the device's new scoring feature, not on human-in-the-loop performance or comparison with human readers.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done:
- Yes, the described tests are essentially standalone performance evaluations of the device's ability to accurately time its alerts and record user input. There is no human interpretation of data involved in the evaluation of these specific functionalities.
7. The Type of Ground Truth Used:
- Audible Signal Timing: Mechanical/digital standard (chronograph).
- Patient Score Recording Accuracy: Known user input/entered data.
8. The Sample Size for the Training Set:
- The document does not mention any training set or machine learning components for the described functionalities. The device's core function of sensing motion is based on an accelerometer, and the new score feature involves timing and data storage, which are deterministic operations.
9. How the Ground Truth for the Training Set Was Established:
- Since no training set is mentioned, this information is not applicable.
§ 882.1400 Electroencephalograph.
(a)
Identification. An electroencephalograph is a device used to measure and record the electrical activity of the patient's brain obtained by placing two or more electrodes on the head.(b)
Classification. Class II (performance standards).