The report, by the Continuity programme, is based on interviews with 187 wearers and the clinicians who treat them, and on the support notices, contracts and firmware licences of four makers.
For three of the four devices, wearers went for up to three years with no support from anyone. The commonest failure was a battery. The most dangerous was a software certificate that expired and locked clinics out of the device.
The report recommends that makers publish a support plan before selling a device and place its firmware with an independent escrow holder. The working group reviewing KF-OS 1 will consider its recommendations.