(44 days)
THE LIFT MASTER ELEVATING POWER SEAT ASSEMBLY DESIGN IS INTENDED FOR USE ON A POWER AND MANUAL WHEELCHAIR. THE LIFT MASTER WILL ELEVATE PATIENTS TO A GREATER HEIGHT THAN THAT OF THE CONVENTIONAL SEAT HEIGHT OF A WHEELCHAIR.
THE LIFT MASTER CONSISTS OF A BALL DRIVE PEDESTAL ACTUATOR WITH A LOAD CAPACITY OF 500 LBS., ALUMINUM AND STEEL BRACKETS, SAFETY CABLE, AND WIRING HARNESS. THE LIFT MASTER BEGINS WITH A SEAT TO FLOOR HEIGHT OF 17 1/2" AND ELEVATES 8" TO AN UPPER LIMIT OF 25 1/2". OTHER RANGES WILL BE AVAILABLE UPON REQUEST. THE SYSTEM HAS A SPEED REDUCTION CAPABILITY WHILE IN THE LIFTED POSITION. THE LIFT MASTER HAS A WEIGHT LIMIT OF 250 LBS. AND A HEIGHT LIMIT OF 6'. OPERATES ON REAR WHEEL DRIVE AND OFFERS CUSTOM SEATING CAPABILITIES.
Acceptance Criteria and Device Performance for the Lift Master System Wheelchair Elevator
The Lift Master System Wheelchair Elevator is designed to enhance the functionality of wheelchairs by allowing elevation of the user. The primary acceptance criteria for this device relate to its stability when in use, particularly when elevated.
1. Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Stability (Non-elevated position): When driven in the recommended position, the Lift Master should have the same stability as the wheelchair manufacturer's had before installation of the Lift Master. | "WHEN DRIVEN IN THE RECOMMENDED POSITION, LIFT MASTER HAS THE SAME STABILITY AS THE WHEELCHAIR MANUFACTURER'S HAD BEFORE INSTALLATION OF THE LIFT MASTER." (Statement indicates compliance without specifying quantitative metrics or comparative data beyond a direct assertion of equivalence). |
| Stability (Elevated position): When driven in the elevated position on terrain with inclines from 0 to 9 degrees, in the designated drive position with the maximum weight limit of 250 lbs., the wheelchair cannot be tipped or turned over. | "WHEN DRIVEN IN THE ELEVATED POSITION ON THE TERRAIN OF 0 DEGREES TO 9 DEGREES, IN THE DESIGNATED DRIVE I POSITION WITH THE MAXIMUM WEIGHT LIMIT OF 250 LBS., THE WHEELCHAIR CAN NOT BE TIPPED OR TURNED OVER AS OUR PHYSICAL TESTING HAS SHOWN UNDER THESE CONDITIONS." (Statement indicates compliance through physical testing demonstrating no tipping or overturning under specified conditions). |
2. Sample Size Used for the Test Set and Data Provenance
The provided document describes "physical testing" but does not specify the sample size (i.e., number of wheelchairs, number of test runs, or number of individuals) used for the test set.
Data Provenance: The data appears to be retrospective as it describes testing already conducted by the manufacturer ("our physical testing has shown"). The country of origin of the data is not explicitly stated, but the manufacturer is based in Katy, TX, USA.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications
There is no mention of experts being used to establish a "ground truth" for the test set in the provided document. The stability claims are based on "physical testing" conducted by the manufacturer.
4. Adjudication Method
No adjudication method is described. The stability claims are presented as direct observations from "physical testing."
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
There is no indication that a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was done. This type of study typically involves human readers (e.g., medical professionals) assessing cases with and without AI assistance to measure improvement in accuracy or efficiency. The Lift Master is a mechanical device, not an AI-powered diagnostic tool, so an MRMC study would not be applicable here.
6. Standalone Performance Study
Yes, a standalone performance study was done. The document explicitly states "NON CLINICAL TESTING: ATTACHMENT." and then details "LIFT MASTER TESTING." This testing was conducted on the device itself ("the wheelchair can not be tipped or turned over as our physical testing has shown") without human interaction as part of the performance evaluation, focusing solely on the device's mechanical stability.
7. Type of Ground Truth Used
The ground truth used for the stability testing was empirical observation/physical testing results. The claims are based on directly observing the device's behavior (whether it tipped or turned over) under controlled conditions, not on expert consensus, pathology, or outcomes data in a medical sense.
8. Sample Size for the Training Set
This question is not applicable. The Lift Master System Wheelchair Elevator is a mechanical device, not an algorithm or AI system that requires a "training set" in the computational sense. The design and engineering would have gone through iterative development and testing, but not "training" with a dataset.
9. How the Ground Truth for the Training Set Was Established
This question is not applicable as there is no "training set" for a mechanical device like the Lift Master. The design and validation would be based on engineering principles, materials science, and physical prototypes.
§ 890.3860 Powered wheelchair.
(a)
Identification. A powered wheelchair is a battery-operated device with wheels that is intended for medical purposes to provide mobility to persons restricted to a sitting position.(b)
Classification. Class II (performance standards).