326 Insomnia
that might in”uence sleep (i.e., exercise, caf feine intake,
smoking, alcohol use). Information is also gathered about en-
vironmental factors (e.g., bed partner, mattress, noise level,
temperature), sleep habits (e.g., watching TV in the bedroom,
staying in bed when awake) and other factors (e.g., stress, va-
cation) that impair/facilitate sleep. In addition, the IIS as-
sesses the impact of insomnia on daytime functioning and
quality of life. Finally, symptoms of other sleep disorders and
psychiatric disorders are evaluated for differential diagnosis.
A detailed clinical interview is important for differential di-
agnosis between insomnia and other sleep pathologies. Several
of these disorders can produce a subjective complaint of in-
somnia, including sleep apnea, periodic limb movements, rest-
less legs syndrome, circadian rhythm disorders, and parasom-
nias. Although a thorough clinical interview can help the
clinician to detect the presence of such disorders, polysomnog-
raphy is almost always necessary to con“rm the diagnosis.
Sleep Diary Monitoring
Self-monitoring of sleep-related variables in a daily diary is
the most widely used method for assessing insomnia. A typ-
ical sleep diary has entries for bedtime, arising time, naps,
medication intake, and for estimates of several sleep para-
meters (time to fall asleep, number and duration of awaken-
ings) and indices of sleep quality and daytime functioning.
The diary can be simpli“ed or adapted to an individual•s spe-
ci“c needs. It is important to review the sleep diary with the
patient and provide corrective feedback, particularly during
the “rst few days of recording. Because of inevitable dis-
crepancies between subjective estimates of sleep parameters
and objective EEG recording, it is important to point out that
only estimates of sleep parameters are expected.
The use of a daily sleep diary has also become a standard
assessment measure in insomnia outcome research. Although
it is subject to some reactivity in the initial phase of use, sleep
diary monitoring has the advantage of providing a prospec-
tive evaluation of an individual•s sleep pattern over an
extended period of time in the home environment. As such, it
may yield a more representative sample of that person•s sleep
than a single night of sleep laboratory assessment. While they
do not re”ect absolute values obtained from polysomno-
graphy, daily estimates of speci“c sleep parameters yield a
reliable and valid relative index of insomnia (Coates et al.,
1982). Speci“cally, sleep diary data provide very useful in-
formation on the nature, frequency, and intensity of insom-
nia, as well as nightly variations of sleep dif“culties, and the
presence of certain perpetuating factors (e.g., naps, spending
too much time in bed). This practical and economical method
is extremely helpful both for initial assessment and for mon-
itoring treatment progress.
PolysomnographyA polysomnographic evaluation involves all-night sleep
monitoring as measured by electroencephalography (EEG),
electrooculography (EOG), and electromyography (EMG).
These three parameters provide the necessary information to
distinguish sleep from wake and to determine the speci“c
sleep stages. Although these three types of recording are gen-
erally suf“cient for monitoring and scoring sleep patterns,
additional parameters (e.g., respiration, electrocardiogram,
oxygen saturation, leg movements) are often assessed, at
least during the “rst night, to detect the presence and severity
of sleep pathologies other than insomnia such as sleep apnea
or periodic limb movement.
Polysomnography provides the most comprehensive
assessment of sleep. It is the only method that allows quan-
ti“cation of sleep stages and that can con“rm or rule out the
presence of another sleep pathology. For insomnia sufferers,
a laboratory evaluation may be helpful for assessing the na-
ture and severity of the sleep problem and to provide data on
the full range of sleep variables from sleep-onset latency to
proportion of time spent in various sleep stages. It is also
useful for determining the level of discrepancy between the
subjective complaints and actual sleep disturbances. Poly-
somnography may also play a therapeutic role in some cases
by showing a patient that he or she is getting more sleep than
actually perceived. Although laboratory polysomnography
is recognized as the •gold standard,Ž it is not without limita-
tions. Because it requires sophisticated equipment and the
presence of a trained technician throughout the night, noc-
turnal polysomnography is expensive, precluding its routine
use. In addition, laboratory polysomnography is a fairly in-
vasive assessment method that may disrupt sleep. Because
individuals are not in their natural environment, they may
sleep differently in the laboratory, especially the “rst night
(the •“rst-night ef fectŽ). In insomnia outcome research, it is
a standard practice to conduct recordings for two or three
consecutive nights and to discard data from the “rst night be-
cause of this reactivity effect. The use of polysomnography
in the assessment of insomnia is still controversial (Edinger
et al., 1989; Jacobs, Reynolds, Kupfer, Lovin, & Ehrenpreis,
1988). A recent practice parameter paper concluded that it
was generally not indicated for the routine evaluation of in-
somnia and that it should be limited to patients for whom the
presence of another sleep disorder is suspected (Sateia,
Doghramji, Hauri, & Morin, 2000).
Several ambulatory monitoring devices have been com-
mercialized for conducting polysomnographic evaluations
in the patient•s home, thereby increasing ecological validity
and reducing the •“rst-night ef fect.Ž The typical portable
recorder is self-contained and allows data storage through-