Diagnostic accuracy of biological markers for detecting obstructive sleep apnoea.

This is a protocol for a Cochrane review (diagnostic). The objectives are as follows: To determine the accuracy of any type of biological marker found in blood, saliva, urine or breath condensation to detect obstructive sleep apnoea (OSA) in adults (> 18 years). Secondary objectives To identify the accuracy of individual biomarkers alone or in combination for detecting OSA. To find the accuracy of biological markers compared to overnight polysomnography (PSG) and home sleep apnoea test (HSAT). To investigate the accuracy of biological markers compared to overnight PSG and to HSAT in people with different degrees of severity of OSA (mild, moderate, severe). To evaluate the accuracy of biomarkers from different sample types to identify OSA.