When a scam works well, scamsters keep at it, and the “someone bought you a free medical alert device” robocall scam aimed at senior citizens is very effective. Even when authorities shut it down, another version pops right up. What if you want to buy a real emergency alert system for yourself or for a loved one, though? There are obviously legitimate companies in that sector, but how do they compare?

Of course, we all know exactly what alert systems do because of the strangely iconic ads that one service ran in past decades. You know the one.

The devices consist of a base station that connects to your phone line and then buttons placed in different spots in the house and/or on a pendant attached to a wrist or worn around the user’s neck. The pendant can work as a tiny speakerphone.

Our safe and secure colleagues down the hall at Consumer Reports determined what consumers should look for in an alert system, and evaluated the features of the best choices in the business. A few important things to look for:

A base station with a good range so you can reach it from anywhere on your property.

A choice of numbers to call: you may not always need an ambulance for every emergency.

The ability to call 911 if you’re not at home but are wearing the pendant.

Battery backup for the base station.

An in-house call center, rather than the company outsourcing it to another firm.

Help buttons that can be mounted in your home, in case you forget to put on the pendant.

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