This trial is enrolling patients who are already being seen at OHSU sleep disorder center or have been referred for clinical reasons by their physician to the OHSU sleep disorder center and are going to have a sleep study that would be paid for by their insurance company for clinical reasons.

The purpose of this study is to determine whether the Portland sleep apnea quiz has a higher specificity and negative predictive value then the Berlin Sleep Questionnaire in a patient population with a high predisposition to sleep apnea presenting to a sleep center.

This trial is enrolling patients who are already being seen at OHSU sleep disorder center or have been referred for clinical reasons by their physician to the OHSU sleep disorder center and are going to have a sleep study that would be paid for by their insurance company for clinical reasons.

400 consecutive adult subjects who have been referred by their doctor to the sleep disorder center and are undergoing a diagnostic sleep study at the OHSU sleep disorders center will be requested to fill out both a Berlin questionnaire and Portland sleep quiz on the night of the initial diagnostic polysomnography. The questionnaires will be collected and scored in a confidential manner. The predictive value of the questionnaires will be compared with the results of overnight polysomnography (Apnea Hypopnea Index).

Inclusion Criteria:

• Adults more than 18 years old

Exclusion Criteria:

• Subjects Unwilling to Complete the Questionnaire

adults presenting to a sleep center