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Postgraduate Education Corner: Contemporary Reviews in Sleep Medicine |

Patient-Reported Outcome Measures for Sleep Disorders and Related ProblemsPatient-Reported Outcome Measures: Sleep Disorders: Clinical and Research Applications FREE TO VIEW

Boris I. Medarov, MD, FCCP; David E. Victorson, PhD; Marc A. Judson, MD, FCCP
Author and Funding Information

From the Division of Pulmonary and Critical Care Medicine (Drs Medarov and Judson), Albany Medical College, Albany, NY; and Department of Medical Social Sciences (Dr Victorson), Northwestern University, Feinberg School of Medicine, Evanston, IL.

Correspondence to: Marc A. Judson, MD, FCCP, Division of Pulmonary and Critical Care Medicine, Albany Medical College, 47 New Scotland Ave, MC-91, Albany, NY 12208; e-mail: judsonm@mail.amc.edu


Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.


Chest. 2013;143(6):1809-1818. doi:10.1378/chest.12-2489
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Patients with sleep disorders are most concerned with the impact of these diseases on their quality of life. Patient-reported outcome (PRO) measurement tools, which assess aspects of a patient’s health status that come directly from the patient, are well suited to evaluate quality of life related to sleep disorders. Although PRO data are subjective, they can be quantified, evaluated for reliability and reproducibility, and used to answer questions of clinical and research importance. This article reviews various PRO measure tools used for sleep disorders in clinical and research settings. These instruments may play a role in screening, diagnosis, and monitoring of various sleep disorders.

Sleep medicine is a relatively young discipline that initially focused on the pathophysiology of sleep (eg, sleep-disordered breathing, arterial blood gas abnormalities), fragmentation of the EEG sleep architecture, and the cardiovascular and neurologic consequences of these derangements.1 Increasing attention is now being directed at the impact of sleep disorders on health-related quality of life, which cannot be directly measured with objective data from comprehensive polysomnography. Although polysomnography data are integral to the diagnosis and treatment of sleep disorders, patients are most concerned about the impact of disease, including cardiovascular and life-threatening complications and functional impairment and emotional stress, on their quality of life.2 This concern has prompted the development of patient-reported outcome (PRO) measurement tools to assess aspects of a patient’s health status that come directly from the patient (ie, without the interpretation of the patient’s responses by a physician or anyone else).3

Unless physician, caregiver, or other proxy versions are necessary, PRO measurement tools are patient administered (ie, self-administered). Generally, they are simple to complete and directly measure the patient’s assessment of quality of life. However, there are inherent problems in accurately quantifying the results of PRO measures.4 The results of a PRO depend on the individual’s cooperation, concentration, education, and heritage. Furthermore, validating and accurately scaling PROs is complicated by inexact reference standards in measuring symptoms as well as complexities in assessing the relationship of PROs to objective measures (eg, the symptom of sleepiness compared with sleep latency).

In addition to PRO measurement tools, other nonperformance-based assessments can be used to evaluate the presence and severity of or comorbid conditions associated with sleep disorders. For example, screening questionnaires for obstructive sleep apnea (OSA) may contain items about the opinions of others (eg, Has the patient been told that he or she snores?) or historical items (eg, weight gain, alcohol use). Such non-PRO data are also useful in the assessment of sleep disorders.

PROs can be evaluated in terms of how accurately they measure the desired trait, their reproducibility, and their internal consistency. Such assessments are outlined in Table 1. PROs may be used in sleep medicine for purposes other than assessment of health-related quality of life. They may play a role in screening, the diagnosis of sleep disorders, and the assessment of the impact of sleep disorders over time. The aim of this review is to provide a detailed summary of the most common sleep-related PRO measurement tools and to discuss their strengths, limitations, and clinical and research applications.

Table Graphic Jump Location
Table 1 —Questionnaire Properties

Sleepiness is a major complaint of patients with sleep disorders and is the most common symptom that prompts individuals with OSA to seek medical attention. Excessive daytime sleepiness (EDS) is the inability to stay awake and alert during regular daytime hours. Sleepiness often impairs psychosocial, intellectual, and work performance5 and is a source of a significant number of traffic and job-related accidents.6 Up to 20% of the general population experiences EDS.7 A tool that accurately quantifies sleepiness could be useful in monitoring the effects of an intervention for a sleep disorder and to screen for potential sleep disorders, thereby obviating the need for polysomnography, which is expensive and time consuming.

Daytime sleep latency (DSL), measured by multiple sleep-latency testing, is considered the gold standard for measuring the propensity to fall asleep.8 An average DSL of <8 min is considered abnormal.9 However, DSL is not synonymous with the symptom of sleepiness.10 Sleepiness also depends on multiple physiologic and psychologic factors, including the level of psychomotor function and the ability to concentrate. Determining the impact of sleepiness should include assessment of the effect of sleepiness on mood, cognition, and motor performance. Therefore, psychomotor vigilance testing, maintenance of wakefulness testing (MWT), and psychologic and cognitive testing should be considered to assess the consequences of sleepiness.11,12 As opposed to the multiple sleep-latency testing, which measures how readily an individual can fall asleep at will, the MWT measures the ability to resist sleep onset. MWT often is administered when alertness is critical for a particular job description (eg, commercial drivers, pilots).11

At times, patients who complain of sleepiness have a normal DSL. Causes for this phenomenon are listed in Table 2, and these conditions should be considered in sleepy patients with a normal DSL and those without significant risk factors for a sleep disorder. Patients with insomnia, for example, often complain of sleepiness but actually show a low propensity to fall asleep and a high-normal DSL. Those individuals are better described as fatigued rather than as sleepy (see the insomnia sections later in this article).

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Table 2 —Causes of Sleepiness With a Normal Sleep Latency
Epworth Sleepiness Scale

The Epworth Sleepiness Scale (ESS)13 is a self-administered sleepiness questionnaire that is simple and time efficient, comprising just eight items. The subject grades the chance of dozing in certain specific situations on a Likert scale of 0 to 3, with the total score ranging from 0 to 24. Higher ESS scores indicate more sleepiness. A score of <10 is considered normal on the basis of the mean+SDs in normal individuals.13

In the initial population in which the ESS was evaluated, the measure reliably distinguished normal subjects from those with various sleep disorders, including sleep apnea, narcolepsy, and idiopathic hypersomnia.13 The ESS score correlated well with DSL.13 In the subgroup of patients with OSA, the ESS score correlated with the severity of the disease as measured by the respiratory disturbance index (RDI) and the minimum nocturnal oxygen saturation. However, recent studies of the ESS have questioned these findings. A study of 1,824 patients undergoing polysomnography showed that there was a small difference (mean, 2.1) in the average ESS score between the group without OSA (RDI <5/h) and the group with severe OSA (RDI ≥30/h).14 This difference is inadequate to reliably distinguish individuals with OSA from those without OSA. Additional studies failed to demonstrate significant clinical correlation between the ESS and measures of OSA.15 Poor agreement has been found between DSL and the ESS in a population with sleep-disordered breathing.16 Therefore, these data suggest that the ESS is an inadequate screening test for OSA.

However, the ESS appears useful in assessing the response to therapy for OSA. Support for this contention is that (1) the statistically significant strong correlation between the ESS score and the severity of OSA that was observed in the initial ESS study population13 has been confirmed in subsequent populations14,17 and (2) the ESS has been shown to have good retest reliability,18 although this has also been challenged by some authors.19 Several studies have found that the test-retest reliability of ESS is less than initially believed.20,21 However, even in those studies, 75% of the subjects showed retest results within 2 points of the original ESS score.

In summary, the ESS is useful to assess the impact of sleepiness on real-life situations and to monitor response to therapy of the patient with OSA. The ESS has limited value in the diagnosis or exclusion of sleep disorders and correlates poorly with objective measurements of the propensity to fall asleep or maintain wakefulness.

Stanford Sleepiness Scale and Karolinska Sleepiness Scale

The Stanford Sleepiness Scale (SSS) is a self-administered PRO measure that requires the subjects to grade their degree of alertness on a scale of 1 to 7.22 As opposed to the ESS, which is a historical assessment of the individual’s propensity to fall asleep, the SSS measures an individual’s current level of alertness. The SSS can be used repeatedly during the day to monitor changes in the subjective level of alertness.23 In some cases, patients who are sleep deprived seem to underestimate their degree of sleepiness, which they classify as mild during periods when they were observed to be intermittently sleeping.24 This may occur through the process of habituation, whereby the effect of a stimulus (in this case, sleep deprivation) is progressively underestimated when that stimulus is applied long term. The SSS is problematic to use clinically because it is time consuming; therefore, it is predominantly used in research studies of acute sleep deprivation. Even though the SSS reflects the level of alertness, it is a poor indicator of individual performance as measured by psychomotor vigilance testing.23

The Karolinska Sleepiness Scale (KSS)25 is a self-administered PRO measure similar to the SSS that assesses sleepiness in real time. The KSS measures nine levels of alertness as opposed to the SSS, which measures seven. The KSS was developed to research EEG findings with sleep deprivation and found to have a strong, though nonlinear correlation with sleep deprivation-associated EEG changes (intrusions of slow eye movements, α and θ activity).25 The advantage of the KSS over the SSS is that the KSS characterizes sleepiness in a greater number of discrete categories so that changes can be more easily detected. The KSS is primarily a research tool because like the SSS, it is too time consuming to be used clinically.

Because polysomnography is expensive and cumbersome, several potential screening tools for OSA have been developed. PRO measures that focus on sleepiness, such as the ESS, lack adequate sensitivity to reliably exclude OSA. This is understandable because sleepiness does not correlate tightly with sleep fragmentation and sleep deprivation related to OSA. Instruments that incorporate OSA risk factors and symptoms other than sleepiness have been developed. Some of the most rigorously studied screening tools for OSA are discussed in this section.

Berlin Sleep Questionnaire

The Berlin Sleep Questionnaire (BSQ)26 is a 10-item self-administered survey to screen for OSA. It incorporates an inventory of several known risk factors for OSA and groups items into the following three categories: snoring behavior, excessive daytime somnolence, and presence of hypertension or obesity. Scoring ≥2 points in the former two categories classifies them as positive. The latter category is positive if either hypertension or obesity is present. Two positive categories indicate a high likelihood of OSA.

Similar to the ESS, the BSQ appeared to be a promising clinical screening tool for OSA in the initial population in which it was studied.26 In this study of 100 subjects, BSQ scores indicating a high risk of OSA had a sensitivity of 0.86 and a specificity of 0.77 for sleep-disordered breathing (RDI >5/h). However, more recent data showed an unacceptable sensitivity of 0.62 for an RDI >10/h, challenging the reliability of the BSQ as an adequate screening test for OSA.27 Although the BSQ has also been proposed to be specifically useful in screening for OSA in preoperative patients,28 a study of 177 subjects of who underwent polysomnography found the sensitivity for moderate to severe apnea to be 78.6%. Such a sensitivity makes it problematic to advocate that the BSQ is a reliable tool to identify patients who may have postoperative complications related to OSA.

The BSQ has been useful in certain specific populations and situations. A high OSA score on the BSQ is associated with resistant hypertension.29 In addition, the BSQ has been embedded in some National Sleep Foundation Sleep in America surveys, which are annual telephone interviews focused on the national demographics of sleep disorders.30

STOP Questionnaire

The STOP questionnaire31 is a screening instrument advocated to detect OSA in preoperative patients. The four-item questionnaire asks the following: S, Do you snore loudly (louder than talking or loud enough to be heard through closed doors); T, do you often feel tired, fatigued, or sleepy during the daytime; O, has anyone observed you stop breathing during your sleep; and P, do you have or are you being treated for high BP? Answering yes to two or more items classifies individuals as high risk for OSA.

The STOP questionnaire was found to have a limited sensitivity of 66%, 74%, and 80% for an apnea-hypopnea index of >5/h, >15/h, and >30/h, respectively.31 The addition of four objective measures—B, BMI >28 kg/m2; A, aged >50 years; N, neck circumference >17 inches for men or >16 inches for women; and G, male sex—to the four STOP questionnaire items (STOP-BANG) (with a high risk for OSA if three or more items are positive items) increased the aforementioned sensitivities to 83.6%, 92.9%, and 100%, respectively.31 Therefore, STOP-BANG appears to be a good screening test for OSA in a preoperative population. In a general population referred for polysomnography, STOP-BANG had a sensitivity of 86.1% for mild OSA, 92.8% for moderate OSA, and 95.6% for severe OSA.32 Therefore, STOP-BANG shows promise as a useful screening tool in the general population for OSA.

Up to 30% of the population reports insomnia symptoms in the preceding month.33 Insomnia has an enormous economic impact and may adversely affect quality of life. Insomnia often is associated with various degrees of fatigue and impaired daytime function, which affected individuals often report as sleepiness. However, people with insomnia actually have a high level of arousal during the day, and their propensity to fall asleep is low as reflected by normal to high sleep latency.34 Insomnia syndromes are a heterogeneous group of disorders comprising primary sleep disorders and psychiatric, medical, and circadian conditions. The disparate nature of insomnia often requires further psychologic, medical, or sleep evaluation and makes establishing the diagnosis challenging. Insomnia is a historical diagnosis consisting of difficulty sleeping or maintaining sleep that results in daytime impairment.35 The gold standard for the diagnosis of insomnia requires a comprehensive interview and review of a sleep diary. Because this process is time consuming, simpler insomnia screening and monitoring instruments have been sought, which have led to the development of a variety of psychometric tools.

Insomnia Symptom Questionnaire

The Insomnia Symptom Questionnaire (ISQ)36 is a self-administered, Likert-scale diagnostic tool. It comprises 13 items that are based on Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, criteria for primary insomnia and has high internal consistency. The ISQ was validated with other PRO measures as a reference as well as with sleep diaries and polysomnographic signs of insomnia.36 The sensitivity of the ISQ for insomnia is poor (10%-76%, depending on the method of confirmation); therefore, it cannot be used reliably as a screening test. However, its specificity uniformly exceeds 90%. These data suggest that the ISQ is a fairly accurate diagnostic tool for insomnia.

Insomnia Severity Index

The Insomnia Severity Index (ISI)37 measures the severity of insomnia and its impact on daily life. It is a seven-item self-administered PRO measure scored on a Likert scale that ranges from 0 to 28, with higher scores suggesting more insomnia. The ISI was found to have relatively high validity, good internal consistency, and reliability compared with similar scales.37 The ISI assumes an established diagnosis of insomnia; therefore, it is not an adequate screening or diagnostic tool. The ISI is useful in detecting changes in the severity and functional impact of insomnia; therefore, it should be considered for monitoring insomnia, including after an intervention.

Pittsburgh Sleep Quality Index

The Pittsburgh Sleep Quality Index (PSQI)38 was introduced to examine sleep quality over a 1-month period. It is a self-administered questionnaire that comprises 19 self-rated questions and five questions rated by a bed partner. The questions explore symptoms of insomnia and other factors affecting sleep quality, such as pain, sleep-disordered breathing, and dyspnea. The maximum score is 21. A PSQI score >5 accurately identifies poor sleepers with a sensitivity of 90% and a specificity of 87% compared with polysomnography. The internal consistency was found to be high.38 The PSQI often is used in clinical practice for assessing and monitoring sleep quality, predominantly in patients with mood disorders. It is also commonly used to evaluate the impact of medical conditions on sleep.39 The PSQI is used in research settings to examine the longitudinal effects of therapeutic interventions for psychiatric or sleep disorders.38

Narcolepsy is a rare disorder that can have an enormous impact on health-related quality of life. Severe EDS is an integral part of narcolepsy and often is disabling. ESS and other sleepiness PRO measures may suggest narcolepsy if severe EDS is identified. However, on the basis of the low prevalence of narcolepsy,40 sleepiness questionnaires should have a poor positive predictive value for this disorder. If a patient fails to exhibit typical cataplexy, the diagnosis of narcolepsy requires comprehensive polysomnography with documentation of severely reduced DSL and evidence of rapid eye movement sleep shortly after sleep onset. For these reasons, narcolepsy is not amenable to screening with a PRO questionnaire.

The Stanford Center for Narcolepsy Sleep Inventory

The Stanford Center for Narcolepsy Sleep Inventory41 is a comprehensive questionnaire comprising 146 items, including ESS items. It inventories clinical data useful for the analysis of patients with narcolepsy but is time consuming to administer and has limited clinical application. Furthermore, the questionnaire does not produce a score; therefore, clinical interpretation of the data are required.

Restless legs syndrome (RLS) is an unpleasant paresthesias experienced mostly in the lower but sometimes in the upper extremities.42 The symptoms tend to occur predominantly at bedtime and can cause discomfort, insomnia, and sleep deprivation in some individuals. These sensations are invariably relieved by movement and exacerbated by rest. Pharmacologic treatment consists of dopamine precursors and agonists as well as antiepileptic drugs, sedatives, and opioids. PRO measures can be used to monitor the severity of RLS-associated symptoms and response to RLS therapy.

The International Restless Legs Syndrome Study Group Rating Scale

The International Restless Legs Syndrome Study Group (IRLS)43 rating scale is a self-administered 10-item PRO measure. Patients are asked to grade the severity, frequency, and impact on sleep of their RLS symptoms. A high score reflects more-severe symptoms. The IRLS rating scale is not a diagnostic tool, and an established diagnosis of RLS is required for its use. The scale is useful in monitoring disease severity and the response to therapy in both clinical and research settings. The IRLS rating scale has high internal consistency, interexaminer reliability, and test-retest reliability.43

The Restless Legs Syndrome Quality of Life Questionnaire

The Restless Legs Syndrome Quality of Life Questionnaire is a self-administered 18-item PRO measure that focuses on the impact of RLS on an individual’s social, work, and sexual functioning.44 A summary score reflecting global quality of life is calculated from 10 of the items and is then transformed to a score of 0 to 100. A higher score indicates better quality of life. The remaining eight items are either categorical or continuous variables specifically about work and sexual interest. The questionnaire was found to reliably measure the impact of RLS on health-related quality of life.44

Sleep disorders cause not only sleep-related symptoms such as somnolence and fatigue but also other physiologic, psychologic, and behavioral disturbances. PROs directed at these problems (eg, depression PROs) may be useful in these cases. A specific discussion of such PROs is beyond the scope of this review.

Health-related quality-of-life PROs and questionnaires have been developed for sleep disorders in general as well as for specific sleep disorders. PROs and questionnaires have also been developed to measure the effects of therapeutic maneuvers, such as nocturnal CPAP, on quality of life. These instruments are discussed next.

Functional Outcomes of Sleep Questionnaire

The Functional Outcomes of Sleep Questionnaire (FOSQ)45 assesses the impact of sleep disorder-related sleepiness on activities of daily living. It is self-administered and comprises 30 items encompassing the following five domains: activity level, vigilance, intimacy and sexual relationships, general productivity, and social outcome. The FOSQ has high internal and test-retest reliability.45 It has been used in both research and clinical settings and is useful for continuous assessment of functional status in individuals receiving therapeutic interventions for sleep disorders. The FOSQ has been a preferred measure to assess the impact of CPAP treatment on OSA.46,47

The FOSQ-1048 is an abbreviated version of the FOSQ, containing 10 items. It appears to have similar validity and reliability as the FOSQ, with an excellent internal consistency. The advantage of the FOSQ-10 over the 30-item FOSQ is that it can be completed in less time; however, the FOSQ-10 has not been as rigorously evaluated.

Calgary Sleep Apnea Quality of Life Index

The Calgary Sleep Apnea Quality of Life Index (SAQLI)49 is a self-administered assessment specifically for OSA. It has 35 standard items organized into the following four domains: daily functioning, social interactions, emotional functioning, and symptoms. The SAQLI also contains an optional fifth domain, treatment-related adverse factors, that is assessed with five additional items. The SAQLI has a demonstrated high degree of internal consistency and is particularly useful to assess the benefit of CPAP and oral appliances in clinical trials of the effect of OSA on quality of life.50,51

Quebec Sleep Questionnaire

The Quebec Sleep Questionnaire (QSQ)52 is a self-administered instrument that has been used in research settings to measure OSA disease-specific quality-of-life PROs. The QSQ comprises the following five domains: hypersomnolence, diurnal symptoms, nocturnal symptoms, emotions, and social interactions. The corresponding domains of the QSQ were shown to correlate well with the ESS, Beck Depression Inventory, and the FOSQ (general productivity and vigilance domains). Compared with the FOSQ, the QSQ appears to be more sensitive in detecting treatment-related improvement of quality of life, which makes the QSQ an attractive measure in OSA intervention trials.52,53 The QSQ was specifically designed for clinical research because the number of items (32) make it somewhat problematic to use in clinical practice.

Patient-Reported Outcomes Information Systems Sleep Disturbance Measure

The National Institutes of Health-sponsored Patient-Reported Outcomes Information Systems (PROMIS) developed two sleep PRO measures: one for sleep disturbances and one for sleep-related impairments.54 These measures were validated and may prove useful for assessing general aspects of sleep and sleep-related impairments in various groups of patients and interventions. However, these measures have not yet being applied in clinical or research settings.

The clinical use of PROs in the management of sleep disorders focuses on three clinical issues: screening, establishing a diagnosis, and monitoring the response to therapy.

Screening

Presently, no questionnaire or PRO measure is adequately sensitive for a sleep disorder to be a reliable screening tool in the general population. In preoperative patients, the STOP-BANG questionnaire appears to be reliable to detect moderate to severe sleep apnea and promising as a screening tool for OSA in the general population. Table 3 lists potential PROs that are useful in screening for various sleep disorders.

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Table 3 —PRO Screening Tools in OSA

EDS = excessive daytime sleepiness; OSA = obstructive sleep apnea; PRO = patient-reported outcome.

Diagnosis

The diagnosis of the majority of sleep disorders involves a detailed medical history and comprehensive polysomnography (ie, OSA, narcolepsy). It is problematic to capture such data in one PRO measure. Few PRO measures have a high enough specificity to be used independently as a diagnostic tool (Table 4) but may be helpful in the diagnosis of specific sleep disorders as part of a comprehensive approach that incorporates additional historical and physiologic data.

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Table 4 —Diagnostic PRO Measures

See Table 3 legend for expansion of abbreviation.

Monitoring Response to Therapy

Several questionnaires and PROs are useful to serially assess the severity of the disease and, hence, are useful to monitor the response to therapy (Table 5). It is not surprising that many PROs perform well in this regard because they are mainly designed to gauge patients’ perceptions of disease impairment on their quality of life. All these questionnaires and PROs have good test-retest reliability. The appropriate questionnaire or PRO to use depends on the underlying sleep disorder (Table 5).

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Table 5 —PRO Measures Used to Monitor Response to Interventions

ESS = Epworth Sleepiness Scale; FOSQ = Functional Outcomes of Sleep Questionnaire; IRLS = International Rest Legs Syndrome Study Group; ISI = Insomnia Severity Index; ISQ = Insomnia Symptom Questionnaire; PSQI = Pittsburgh Sleep Quality Index; QSQ = Quebec Sleep Questionnaire; RLS = restless legs syndrome; RLSQoL = Restless Legs Syndrome Quality of Life Questionnaire; SAQLI = Sleep Apnea Quality of Life Index; SSS = Stanford Sleepiness Scale. See Table 3 legend for expansion of other abbreviations.

Sleep disorders have a great impact on health-related quality of life because they impair an individual’s normal function, mood, and well-being, making their assessment of paramount importance to patients. A large number of PRO measures have been developed for the screening and diagnosis of sleep disorders, assessment of the severity of patient symptoms, and assessment of the functional limitations caused by sleep disorders; thus, they have an integral place in the clinical management and research of sleep disorders. It is expected that these measures will become further refined and focused on specific sleep disorders in the future.

Financial/nonfinancial disclosures: The authors have reported to CHEST the following conflicts of interest: Dr Judson is a consultant for Pulmonary Reviews; Janssen Biotech, Inc; and Celgene Corporation. Drs Medarov and Victorson have reported that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.

BSQ

Berlin Sleep Questionnaire

DSL

daytime sleep latency

EDS

excessive daytime sleepiness

ESS

Epworth Sleepiness Scale

FOSQ

Functional Outcomes of Sleep Questionnaire

IRLS

International Restless Legs Syndrome Study Group

ISI

Insomnia Severity Index

ISQ

Insomnia Symptom Questionnaire

KSS

Karolinska Sleepiness Scale

OSA

obstructive sleep apnea

PRO

patient-reported outcome

PSQI

Pittsburgh Sleep Quality Index

QSQ

Quebec Sleep Questionnaire

RDI

respiratory disturbance index

RLS

restless legs syndrome

SAQLI

Sleep Apnea Quality of Life Index

SSS

Stanford Sleepiness Scale

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Chung F, Yegneswaran B, Liao P, et al. Validation of the Berlin questionnaire and American Society of Anesthesiologists checklist as screening tools for obstructive sleep apnea in surgical patients. Anesthesiology. 2008;108(5):822-830. [CrossRef] [PubMed]
 
Gus M, Gonçalves SC, Martinez D, et al. Risk for obstructive sleep apnea by Berlin questionnaire, but not daytime sleepiness, is associated with resistant hypertension: a case-control study. Am J Hypertens. 2008;21(7):832-835. [CrossRef] [PubMed]
 
Hiestand DM, Britz P, Goldman M, Phillips B. Prevalence of symptoms and risk of sleep apnea in the US population: results from the National Sleep Foundation Sleep in America 2005 poll. Chest. 2006;130(3):780-786. [CrossRef] [PubMed]
 
Chung F, Yegneswaran B, Liao P, et al. STOP questionnaire: a tool to screen patients for obstructive sleep apnea. Anesthesiology. 2008;108(5):812-821. [CrossRef] [PubMed]
 
Ong TH, Raudha S, Fook-Chong S, Lew N, Hsu AA. Simplifying STOP-BANG: use of a simple questionnaire to screen for OSA in an Asian population. Sleep Breath. 2010;14(4):371-376. [CrossRef] [PubMed]
 
Morin CM, LeBlanc M, Daley M, Gregoire JP, Mérette C. Epidemiology of insomnia: prevalence, self-help treatments, consultations, and determinants of help-seeking behaviors. Sleep Med. 2006;7(2):123-130. [CrossRef] [PubMed]
 
Bonnet MH, Arand DL. Hyperarousal and insomnia. Sleep Med Rev. 1997;1(2):97-108. [CrossRef] [PubMed]
 
American Academy of Sleep Medicine. The International Classification of Sleep Disorders: Diagnostic and Coding Manual. Westchester, IL: American Academy of Sleep Medicine; 2001.
 
Okun ML, Kravitz HM, Sowers MF, Moul DE, Buysse DJ, Hall M. Psychometric evaluation of the Insomnia Symptom Questionnaire: a self-report measure to identify chronic insomnia. J Clin Sleep Med. 2009;5(1):41-51. [PubMed]
 
Bastien CH, Vallières A, Morin CM. Validation of the Insomnia Severity Index as an outcome measure for insomnia research. Sleep Med. 2001;2(4):297-307. [CrossRef] [PubMed]
 
Buysse DJ, Reynolds CF III, Monk TH, Berman SR, Kupfer DJ. The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Res. 1989;28(2):193-213. [CrossRef] [PubMed]
 
Osorio CD, Gallinaro AL, Lorenzi-Filho G, Lage LV. Sleep quality in patients with fibromyalgia using the Pittsburgh Sleep Quality Index. J Rheumatol. 2006;33(9):1863-1865. [PubMed]
 
Hublin C, Kaprio J, Partinen M, et al. The prevalence of narcolepsy: an epidemiological study of the Finnish Twin Cohort. Ann Neurol. 1994;35(6):709-716. [CrossRef] [PubMed]
 
Anic-Labat S, Guilleminault C, Kraemer HC, Meehan J, Arrigoni J, Mignot E. Validation of a cataplexy questionnaire in 983 sleep-disorders patients. Sleep. 1999;22(1):77-87. [PubMed]
 
Ekbom KA. Restless legs syndrome. Neurology. 1960;10:868-873. [CrossRef] [PubMed]
 
Walters AS, LeBrocq C, Dhar A, et al; International Restless Legs Syndrome Study Group. Validation of the International Restless Legs Syndrome Study Group rating scale for restless legs syndrome. Sleep Med. 2003;4(2):121-132. [CrossRef] [PubMed]
 
Abetz L, Vallow SM, Kirsch J, Allen RP, Washburn T, Earley CJ. Validation of the Restless Legs Syndrome Quality of Life questionnaire. Value Health. 2005;8(2):157-167. [CrossRef] [PubMed]
 
Weaver TE, Laizner AM, Evans LK, et al. An instrument to measure functional status outcomes for disorders of excessive sleepiness. Sleep. 1997;20(10):835-843. [PubMed]
 
Barnes M, Houston D, Worsnop CJ, et al. A randomized controlled trial of continuous positive airway pressure in mild obstructive sleep apnea. Am J Respir Crit Care Med. 2002;165(6):773-780. [CrossRef] [PubMed]
 
Faccenda JF, Mackay TW, Boon NA, Douglas NJ. Randomized placebo-controlled trial of continuous positive airway pressure on blood pressure in the sleep apnea-hypopnea syndrome. Am J Respir Crit Care Med. 2001;163(2):344-348. [CrossRef] [PubMed]
 
Chasens ER, Ratcliffe SJ, Weaver TE. Development of the FOSQ-10: a short version of the Functional Outcomes of Sleep Questionnaire. Sleep. 2009;32(7):915-919. [PubMed]
 
Flemons WW, Reimer MA. Development of a disease-specific health-related quality of life questionnaire for sleep apnea. Am J Respir Crit Care Med. 1998;158(2):494-503. [CrossRef] [PubMed]
 
Siccoli MM, Pepperell JC, Kohler M, Craig SE, Davies RJ, Stradling JR. Effects of continuous positive airway pressure on quality of life in patients with moderate to severe obstructive sleep apnea: data from a randomized controlled trial. Sleep. 2008;31(11):1551-1558. [PubMed]
 
Flemons WW, Reimer MA. Measurement properties of the Calgary Sleep Apnea Quality of Life Index. Am J Respir Crit Care Med. 2002;165(2):159-164. [CrossRef] [PubMed]
 
Lacasse Y, Bureau MP, Sériès F. A new standardised and self-administered quality of life questionnaire specific to obstructive sleep apnoea. Thorax. 2004;59(6):494-499. [CrossRef] [PubMed]
 
Flemons WW. Measuring quality of life in patients with sleep apnoea: whose life is it anyway? Thorax. 2004;59(6):457-458. [CrossRef] [PubMed]
 
Buysse DJ, Yu L, Moul DE, et al. Development and validation of patient-reported outcome measures for sleep disturbance and sleep-related impairments. Sleep. 2010;33(6):781-792. [PubMed]
 

Figures

Tables

Table Graphic Jump Location
Table 1 —Questionnaire Properties
Table Graphic Jump Location
Table 2 —Causes of Sleepiness With a Normal Sleep Latency
Table Graphic Jump Location
Table 3 —PRO Screening Tools in OSA

EDS = excessive daytime sleepiness; OSA = obstructive sleep apnea; PRO = patient-reported outcome.

Table Graphic Jump Location
Table 4 —Diagnostic PRO Measures

See Table 3 legend for expansion of abbreviation.

Table Graphic Jump Location
Table 5 —PRO Measures Used to Monitor Response to Interventions

ESS = Epworth Sleepiness Scale; FOSQ = Functional Outcomes of Sleep Questionnaire; IRLS = International Rest Legs Syndrome Study Group; ISI = Insomnia Severity Index; ISQ = Insomnia Symptom Questionnaire; PSQI = Pittsburgh Sleep Quality Index; QSQ = Quebec Sleep Questionnaire; RLS = restless legs syndrome; RLSQoL = Restless Legs Syndrome Quality of Life Questionnaire; SAQLI = Sleep Apnea Quality of Life Index; SSS = Stanford Sleepiness Scale. See Table 3 legend for expansion of other abbreviations.

References

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Chung F, Yegneswaran B, Liao P, et al. Validation of the Berlin questionnaire and American Society of Anesthesiologists checklist as screening tools for obstructive sleep apnea in surgical patients. Anesthesiology. 2008;108(5):822-830. [CrossRef] [PubMed]
 
Gus M, Gonçalves SC, Martinez D, et al. Risk for obstructive sleep apnea by Berlin questionnaire, but not daytime sleepiness, is associated with resistant hypertension: a case-control study. Am J Hypertens. 2008;21(7):832-835. [CrossRef] [PubMed]
 
Hiestand DM, Britz P, Goldman M, Phillips B. Prevalence of symptoms and risk of sleep apnea in the US population: results from the National Sleep Foundation Sleep in America 2005 poll. Chest. 2006;130(3):780-786. [CrossRef] [PubMed]
 
Chung F, Yegneswaran B, Liao P, et al. STOP questionnaire: a tool to screen patients for obstructive sleep apnea. Anesthesiology. 2008;108(5):812-821. [CrossRef] [PubMed]
 
Ong TH, Raudha S, Fook-Chong S, Lew N, Hsu AA. Simplifying STOP-BANG: use of a simple questionnaire to screen for OSA in an Asian population. Sleep Breath. 2010;14(4):371-376. [CrossRef] [PubMed]
 
Morin CM, LeBlanc M, Daley M, Gregoire JP, Mérette C. Epidemiology of insomnia: prevalence, self-help treatments, consultations, and determinants of help-seeking behaviors. Sleep Med. 2006;7(2):123-130. [CrossRef] [PubMed]
 
Bonnet MH, Arand DL. Hyperarousal and insomnia. Sleep Med Rev. 1997;1(2):97-108. [CrossRef] [PubMed]
 
American Academy of Sleep Medicine. The International Classification of Sleep Disorders: Diagnostic and Coding Manual. Westchester, IL: American Academy of Sleep Medicine; 2001.
 
Okun ML, Kravitz HM, Sowers MF, Moul DE, Buysse DJ, Hall M. Psychometric evaluation of the Insomnia Symptom Questionnaire: a self-report measure to identify chronic insomnia. J Clin Sleep Med. 2009;5(1):41-51. [PubMed]
 
Bastien CH, Vallières A, Morin CM. Validation of the Insomnia Severity Index as an outcome measure for insomnia research. Sleep Med. 2001;2(4):297-307. [CrossRef] [PubMed]
 
Buysse DJ, Reynolds CF III, Monk TH, Berman SR, Kupfer DJ. The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Res. 1989;28(2):193-213. [CrossRef] [PubMed]
 
Osorio CD, Gallinaro AL, Lorenzi-Filho G, Lage LV. Sleep quality in patients with fibromyalgia using the Pittsburgh Sleep Quality Index. J Rheumatol. 2006;33(9):1863-1865. [PubMed]
 
Hublin C, Kaprio J, Partinen M, et al. The prevalence of narcolepsy: an epidemiological study of the Finnish Twin Cohort. Ann Neurol. 1994;35(6):709-716. [CrossRef] [PubMed]
 
Anic-Labat S, Guilleminault C, Kraemer HC, Meehan J, Arrigoni J, Mignot E. Validation of a cataplexy questionnaire in 983 sleep-disorders patients. Sleep. 1999;22(1):77-87. [PubMed]
 
Ekbom KA. Restless legs syndrome. Neurology. 1960;10:868-873. [CrossRef] [PubMed]
 
Walters AS, LeBrocq C, Dhar A, et al; International Restless Legs Syndrome Study Group. Validation of the International Restless Legs Syndrome Study Group rating scale for restless legs syndrome. Sleep Med. 2003;4(2):121-132. [CrossRef] [PubMed]
 
Abetz L, Vallow SM, Kirsch J, Allen RP, Washburn T, Earley CJ. Validation of the Restless Legs Syndrome Quality of Life questionnaire. Value Health. 2005;8(2):157-167. [CrossRef] [PubMed]
 
Weaver TE, Laizner AM, Evans LK, et al. An instrument to measure functional status outcomes for disorders of excessive sleepiness. Sleep. 1997;20(10):835-843. [PubMed]
 
Barnes M, Houston D, Worsnop CJ, et al. A randomized controlled trial of continuous positive airway pressure in mild obstructive sleep apnea. Am J Respir Crit Care Med. 2002;165(6):773-780. [CrossRef] [PubMed]
 
Faccenda JF, Mackay TW, Boon NA, Douglas NJ. Randomized placebo-controlled trial of continuous positive airway pressure on blood pressure in the sleep apnea-hypopnea syndrome. Am J Respir Crit Care Med. 2001;163(2):344-348. [CrossRef] [PubMed]
 
Chasens ER, Ratcliffe SJ, Weaver TE. Development of the FOSQ-10: a short version of the Functional Outcomes of Sleep Questionnaire. Sleep. 2009;32(7):915-919. [PubMed]
 
Flemons WW, Reimer MA. Development of a disease-specific health-related quality of life questionnaire for sleep apnea. Am J Respir Crit Care Med. 1998;158(2):494-503. [CrossRef] [PubMed]
 
Siccoli MM, Pepperell JC, Kohler M, Craig SE, Davies RJ, Stradling JR. Effects of continuous positive airway pressure on quality of life in patients with moderate to severe obstructive sleep apnea: data from a randomized controlled trial. Sleep. 2008;31(11):1551-1558. [PubMed]
 
Flemons WW, Reimer MA. Measurement properties of the Calgary Sleep Apnea Quality of Life Index. Am J Respir Crit Care Med. 2002;165(2):159-164. [CrossRef] [PubMed]
 
Lacasse Y, Bureau MP, Sériès F. A new standardised and self-administered quality of life questionnaire specific to obstructive sleep apnoea. Thorax. 2004;59(6):494-499. [CrossRef] [PubMed]
 
Flemons WW. Measuring quality of life in patients with sleep apnoea: whose life is it anyway? Thorax. 2004;59(6):457-458. [CrossRef] [PubMed]
 
Buysse DJ, Yu L, Moul DE, et al. Development and validation of patient-reported outcome measures for sleep disturbance and sleep-related impairments. Sleep. 2010;33(6):781-792. [PubMed]
 
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