A systematic review of screening questionnaires for obstructive sleep apnea.

PURPOSE: Obstructive sleep apnea (OSA) may lead to life-threatening problems if it is left undiagnosed. Polysomnography is the "gold standard" for OSA diagnosis; however, it is expensive and not widely available. The objective of this systematic review is to identify and evaluate the available questionnaires for screening OSA.

SOURCE: We carried out a literature search through MEDLINE, EMBASE, and CINAHL to identify eligible studies. The methodological validity of each study was assessed using the Cochrane Methods Group's guideline.

PRINCIPAL FINDINGS: Ten studies (n = 1,484 patients) met the inclusion criteria. The Berlin questionnaire was the most common questionnaire (four studies) followed by the Wisconsin sleep questionnaire (two studies). Four studies were conducted exclusively on "sleep-disorder patients", and six studies were conducted on "patients without history of sleep disorders". For the first group, pooled sensitivity was 72.0% (95% confidence interval [CI]: 66.0-78.0%; I(2) = 23.0%) and pooled specificity was 61.0% (95% CI: 55.0-67.0%; I(2) = 43.8%). For the second group, pooled sensitivity was 77.0% (95% CI: 73.0-80.0%; I(2) = 78.1%) and pooled specificity was 53.0% (95% CI: 50-57%; I(2) = 88.8%). The risk of verification bias could not be eliminated in eight studies due to insufficient reporting. Studies on snoring, tiredness, observed apnea, and high blood pressure (STOP) and STOP including body mass index, age, neck circumference, gender (Bang) questionnaires had the highest methodological quality.

CONCLUSION: The existing evidence regarding the accuracy of OSA questionnaires is associated with promising but inconsistent results. This inconsistency could be due to studies with heterogeneous design (population, questionnaire type, validity). STOP and STOP-Bang questionnaires for screening of OSA in the surgical population are suggested due to their higher methodological quality and easy-to-use features.