I've found a little gadget that makes it less likely that my Alzheimer's Mom will go outside without my knowledge. It is a doorknob alarm that activates when Mom touches it, and stops as soon as she takes her hand away. This might deter her from going out, and if she does decide to leave anyway, the alarm will let me know.
Amazon has similar alarms, and they don't good reviews because they aren't supposed to be used on metal doors. I'm not sure why this is; perhaps contact with the metal of the door could conduct a static charge somewhat like a touch lamp, and activate the alarm? Our door is metal and we've had no trouble thus far, but the door is protected by a screen door on the outside.
Thus far I've remembered to switch the alarm off before I feed the outdoor cats each morning. I'll probably forget eventually but the alarm will quickly remind me.
I'm pleased with this simple and inexpensive alarm that adds another layer of protection for Mom.