Btw, it's also possible for the lab environment to be unrealistically bad. You have all these electrodes and wires attached to your head and other body parts, sleeping in an unfamiliar environment, if you need to use the bathroom then you have to tell the technician to come unhook you from the wires and then re-hook you when you're back... and on the subject of bright LEDs, there were a couple in the room that I covered up with spare items of clothing the last time I got a sleep study.

But yes, there might well be much worse problems at home. I think a lab sleep study is best suited for detecting problems like sleep apnea, where it doesn't matter when you fell asleep as long as you did eventually. Though even for that, you'd probably have to make sure your sleeping position is about the same.