The more extreme data mart strategy is that of the completely stand alone data mart, the concept being that its fast, easy, cheap, and delivers value immediately. I'm a supporter of this at the desktop level- thats the point of the Datamartist tool afterall.
Sleep studies are tests that record what happens to your body during sleep. The studies are done to find out what is causing your sleep problems. Sleep studies can also determine whether you have a problem with your stages of sleep. The two main types of sleep are non-rapid eye movement (NREM) and rapid eye movement (REM). Normally, NREM and REM alternate 4 to 5 times during a night's sleep.
A number of tests can be carried out to assess your sleep and help identify any underlying cause. These are usually carried out at a specialist sleep centre. Two of the main tests used are: Polysomnography (a night time sleep test), which will help rule out sleep disorders such as narcolepsy or sleep apnoea.