This overall score is made up of: reception and tracking (50%) and ease of use (50%).

We assess the user manual, email and telephone support and SIM insertion, where necessary. We also assess configuring, activating an SOS, recharging, using the buttons, the shape of the device and whether it is easy to grip and carry.

We call to and from the device, to test whether the voice quality was clear and loud enough to hear.

We test their mobile network reception, GPS accessibility, and battery life to find which ones perform the best.

Old models tested under a pass/fail methodology. New models were assessed for their effectiveness, which is why they have a score. These results do not contribute to the overall score. NA means they don't have this feature.

As with any device powered by batteries, personal alarms only have a limited amount of time before needing recharging.

We measured battery life using the most power-hungry settings on each device. The times listed here represent the extreme end of usage.

Look for a higher second digit in the IP rating which indicates better protection.

Price at time of purchase.

Geo-fencing allows you to set up a virtual fence and alarm for when it is crossed.

If you need to configure the device, what options does it give you? SMS, app or website?

Look for a personal alarm with the capability to define more than one contact. The more contacts you have, the more useful it is in case the first contact is away from their phone.

A charging cradle is useful because it makes it obvious the device needs to be plugged in.

Does the device accept incoming calls?

Will the device auto-accept an incoming call? This would be useful if the user has fallen or is unable to move but able to speak.

Activates if the device falls rapidly – which then triggers an alarm to a contact.

Sends an alarm to a contact if the device doesn't move for a specified amount of time.

This is where you can set the device to tell you whether it has moved. Sort of the opposite of the non-movement alarm.

If the device starts moving rapidly, say by the wearer getting into a car or train, it creates an alarm to send to a contact with this information.