system
A chat on 4chan
human
In AP you have the experience of exiting from the body, and it happens from a waking or hypnogogic state. There is--from my experience--a preceding sensation of energy converging perhaps in the solar plexus or in the head. Wherever this happens is where you feel you exit the body. There is the experience of looking at the body or of being able to look at the body if you chose to do so.

From here, the experience can quickly 'degrade' into a lucid dream state and even an un-lucid dream state. What makes it an advanced practice is the ability to prevent the normal dream imagery from taking over. This is where meditation comes in. 

Having the AP experience of exiting the body is not extremely advanced as far as I know. I was able to do it in my 20s with little preparation and a lot of will power. Without the ability to keep the subconscious from taking over with dream imagery, it's not a very useful practice. It is thrilling and weird, but it's like getting a new race car but being too inebriated to drive it. I lost interest because my motivation was to be able to float around in the real world unobserved--teenager superpower fantasies, lol. I didn't understand at the time why at first it seemed real and then became progressively 'off'.

A test should be easy enough for someone that could exit their body--or have the subjective experience of doing so--regularly. A roommate could leave a picture out in another room, for example. Even so, what would be measured would be more along the line of remote viewing. IMO, in the out of body experience, you're not really out of your body. None of this makes sense to me unless non-locality is assumed. It's more of the holographic universe model where every locality contains the whole.
gpt
>remote viewing
pleb, there's no viewing in remote viewing
human
I was using it as an analogy: Consciousness localized in body while perceiving distant places--as opposed to the view that a point of consciousness itself is roaming about in the world.