Sarmad,
Thanks for expressing interest in the MESA actigraphy data. For someone new to the area, I would recommend exploring the summarized actigraphy data first. There you will find variables that describe the average amount of time spent asleep and awake (along with lots of other variables) over the time that the study participant wore the actigraphy watch. Datasets can be downloaded from the files area with an approved DAUA.
The first variable you are looking for is probably avgmainsleep5
.
If you were looking to explore the raw actigraphy files (30-seconds of data per row) then this would require more explanation. I would suggest starting with the Scoring Manual and Manual of Procedures linked from the main documentation page.
Thanks,
Mike
Sarmad,
The Actigraphy Introduction contains some of this information.
interval
column. Sleep time and wake time can be identified where interval = REST
.Mike