understanding "minutesToFallAsleep"

[sjmerel]

We are collaborating on a medical research study, and the team had some questions about the "minutesToFallAsleep" quantity.

We have found that this number is almost always 0, which is expected from what the docs say:

This value is generally 0 for autosleep created sleep logs.

Does "autosleep created" just mean that the onset of sleep is detected automatically by the Fitbit?  What is a situation where a sleep log would not be created this way, and would result in a nonzero minutesToFallAsleep?   Is there any way to reliably measure this value with a Fitbit?

[Gordon-C]

Hi @sjmerel 

You are correct that minutesToFallAsleep will almost always be 0 (zero).  "auto_detected" sleep log is one generated by the Fitbit device.   We don't have a method for the user to log when they get into bed and the device still track sleep stages to get a positive minutesToFallAsleep value.   

Gordon