Daytime polysomnogram diagnosis of sleep disorders.

The daytime polysomnogram was used to evaluate 310 consecutive patients with suspected sleep disorders, referred mainly because of excessive daytime sleepiness. Abnormalities consistent with pathologic sleep apnoea were present in 102 cases, and with narcolepsy-cataplexy in 49 cases. The daytime polysomnogram is a readily accessible, accurate, and cost-effective method for diagnosing many sleep disorders.