TABLE 14.2 Summary of Advantages and Limitations of Different Sleep Assessment Modalities
Assessment Modality Instruments Advantages LimitationsSemistructured Interviews
Sleep Diary
Self-Report Measures
Mechanical Devices
Laboratory
polysomnography
Portable polysomnography
Insomnia Interview Schedule
(Morin, 1993).
Structured Interview for Sleep
Disorders (Schramm et al.,
1993).Sleep Impairment Index
(Morin, 1993).
Pittsburgh Sleep Quality Index
(Buysse et al., 1989).
Dysfunctional Beliefs and Atti-
tudes about Sleep Scale
(Morin, 1994).
Wrist actigraphy.
Sleep assessment device.
Switch-activated clock.Provides detailed information about the na-
ture, course, and severity of the sleep
disturbance and associated aspects. Allows a
functional analysis and differential diagnosis.Assesses nightly variations in the nature, fre-
quency, and severity of sleep dif“culties, and
some maladaptive behaviors. Flexible. Good
ecological validity. Allows prospective evalua-
tion over extensive periods of time. Excellent
outcome measure. Economical.
Practical and economical. No need for trained
staff. Can be administered repeatedly and used
as an outcome measure.Self-administered. No need for a trained
technician. Economical. Unobtrusive.
Ecological validity.The •gold standardŽ for the evaluation and
diagnosis of all sleep disorders. Provides
objective measures for the entire range of
sleep parameters, including sleep stages.Same advantages as laboratory polysomnog-
raphy. Ecological validity. Reduction of the
•“rst-night ef fect.ŽRequires substantial knowledge of the
sleep disorders spectrum and inter-
viewer training. Time consuming.Signi“cant discrepancies with
polysomnography. Reactivity and
noncompliance in some individuals.Retrospective and global assessment.
Risk of overestimation of sleep
dif“culties. Most instruments not fully
validated.Does not measure sleep stages.
Convergent validity with polysom-
nography needs to be studied further.Expensive. Trained technician needed
throughout the night and to score data.
Relatively invasive. Low ecological
validity. Need for repeated measures to
reliability assess insomnia. •First-night
effect.Ž
Higher risk of artifacts and invalida-
tion. Lack of behavioral observations.Evaluation of Sleep Complaints/Disorders 325tion can also be useful to corroborate the subjective com-
plaints and to rule out the presence of other sleep disorders.
Table 14.2 presents a list of insomnia measures with their re-
spective advantages and limitations.
Clinical Interview
The clinical interview is the most important component of in-
somnia assessment. It elicits detailed information about the
nature of the complaint, its severity, course, potential causes,
and symptoms, as well as evidence of other sleep disorders,
exacerbating and alleviating factors, and previous treatments
including medication (Morin & Edinger, 1997; Spielman &
Glovinsky, 1997). A functional analysis aims to identify pre-
disposing, precipitating, and perpetuating factors of insom-
nia. It is important to inquire about life events, psychological
disorders, substance use, and medical illnesses at the time of
onset of the sleep problem to help establish etiology. Of par-
ticular importance for treatment planning is the identi“cation
of factors that contribute to perpetuating sleep dif“culties,
such as maladaptive sleep habits (e.g., spending too much
time in bed) and dysfunctional cognitions (e.g., worrying
excessively about the consequences of insomnia).
Two interviews available to gather this type of informa-
tion in a structured format are the Structured Interview for
Sleep Disorders (Schramm et al., 1993), which is helpful in
establishing a preliminary differential diagnosis among the
different sleep disorders, and the Insomnia Interview Sched-
ule (IIS; Morin, 1993), which is more speci“cally designed
for patients with a suspected diagnosis of primary or sec-
ondary insomnia. The IIS gathers a wide range of information
about the nature and severity of the sleep problem, and the
current sleep/wake schedule, which includes information
such as typical bedtime and arising times, time of the last
awakening in the morning, frequency and duration of day-
time naps, frequency of dif“culties sleeping, time taken to
fall asleep, number and duration of awakenings per night, and
total duration of sleep. The IIS also assesses the onset (e.g.,
gradual or sudden, precipitating events), course (e.g., persis-
tent, episodic, seasonal), and duration of insomnia, past and
current use of sleeping aids (i.e., prescribed and over-the-
counter medications, alcohol), as well as health habits