Table 2 Currently available measurement systems for sleep and circadian rhythms
Measurement system | Key features | Proposed use |
|---|---|---|
Self-report | Prolonged reporting (for example, two weeks or more) of sleep timing, latency, quality and duration, daily mood, daytime physical activity | - Identification of insomnia, dysfunctional sleep and circadian-rhythms. |
Cross sectional questionnaires of sleep quality, excessive daytime sleepiness, fatigue, presence of sleep disordered breathing and circadian rhythms; | - Characterization of the sleep-wake cycle. | |
Smart phone technologies now allow daily recording of sleep schedules and disturbances, as well as daytime physical activity patterns | - Assessment of treatment response. | |
Polysomnography | Laboratory or ambulatory monitoring of nocturnal sleep | - Differential diagnosis of various sleep disorders. |
- Characterization of sleep macro/microarchitecture. | ||
Actigraphy | Indirect measure of the sleep-wake cycle especially convenient for multiday ambulatory assessment | - Identification of insomnia, dysfunctional sleep and circadian rhythms. |
At least one week of monitoring, (including weekdays and weekends) | - Characterization of the sleep-wake cycle. | |
Key differentiation of patterns of sleep onset, offset, daytime activity and napping | - Assessment of treatment response. | |
Some monitors can simultaneously record patterns of light exposure and estimate energy expenditure | ||
Melatonin assays | Dim light melatonin onset protocol in controlled laboratory settings or at home | - Characterization of circadian rhythms |
- Assessment of treatment response. | ||
From saliva, urine or blood | - Can support diagnosis of some circadian rhythm sleep disorders | |
Core body temperature monitoring | 24-hour recording in controlled laboratory settings | - Characterization of circadian rhythms |
- Assessment of treatment response | ||
From ingested wireless probe or rectal probe | - Can support diagnosis of some circadian rhythm sleep disorders | |
Cortisol assays | 24-hour recording | - Characterization of circadian rhythms |
From saliva, urine or blood | - Assessment of treatment response | |
Vigilance monitoring | 24-hour recording in controlled laboratory settings | - Characterization of circadian rhythms |
- Psychomotor Vigilance Task (PVT) | - Assessment of treatment response | |
- Wake EEG | ||
- Multiple Sleep Latency test | ||
The PVT or similar tasks are now available on smart phone applications | ||
Cardiovascular monitoring | Continuous or repeated measures of blood pressure and heart rate parameters across 24 hours in controlled laboratory settings | - Characterization of circadian rhythms |
- Assessment of treatment response |