Not sure if we are going to do this study now.

The primary objective of the proposed study is to investigate the agreement levels of modern and well-established actigraphy devices against PSG in healthy as well as patient populations for multiple sleep parameters across two study sites (Qatar and New York City).

The importance of sleep upon physiological and psychological health has been extensively documented. It has been proposed that adequate sleep, as well as good sleep quality, is vital for wellbeing. (1). Some have suggested that sleep curtailment has paralleled the increased prevalence of cardiometabolic disease including obesity (2), type 2 diabetes mellitus (3, 4), hypertension (5, 6) and more. Sleep researchers face a major challenge since there are multiple methods for sleep assessment, all of which have advantages and disadvantages.Whilst polysomnography (PSG) is considered to be the gold standard for sleep assessment, there are some limitations including laboratory attendance for the participant and sleep scoring variance. Sleep questionnaires are widely utilized, particularly in large epidemiological studies, but are susceptible to inaccuracies and some have not been validated against PSG. Wrist actigraphy has provided researchers with an attractive equivalent and there are now multiple commercial manufacturers available. Actigraphic devices are usually worn on the non-dominant wrist and the instrument is used to monitor wrist movements through the use of an accelerometer and a memory chip. Wrist actigraphy is useful in the detection of sleep, wake, and activity.

Inclusion Criteria:

• Attending a regularly scheduled Polysomnography test at Weill Cornell Medical College. Male or female. 18-80 years old

Exclusion Criteria:

• Not attending a regularly scheduled Polysomnography test at Weill Cornell Medical College. Under 18 or over 80 years old. Pregnancy. Unable to provide informed consent.