What is the total wake time (TWT), in minutes?

What is the total wake time (TWT), in minutes?

• A. 25
• B. 15
• C. 100
• D. 85

Answer: (D)

Total wake time is the total amount of time the patient is awake during the sleep record. In sleep scoring, the night is broken into 30-second epochs, and every epoch scored as wake adds 0.5 minutes to TWT. By summing all wake epochs from lights out to lights on, you obtain the total wake time. Here, the wake periods across the night add up to 85 minutes, so the total wake time is 85 minutes. This measure helps gauge sleep continuity and feeds into sleep efficiency calculations (sleep efficiency = total sleep time divided by time in bed, times 100).

Total wake time is the total amount of time the patient is awake during the sleep record. In sleep scoring, the night is broken into 30-second epochs, and every epoch scored as wake adds 0.5 minutes to TWT. By summing all wake epochs from lights out to lights on, you obtain the total wake time. Here, the wake periods across the night add up to 85 minutes, so the total wake time is 85 minutes. This measure helps gauge sleep continuity and feeds into sleep efficiency calculations (sleep efficiency = total sleep time divided by time in bed, times 100).