 Recent studies found that the non-contact screening device SleepMinder (ResMed Sensor Technologies, Dublin, Ireland) detects sleep-disordered breathing (SDB) with high diagnostic accuracy in cohorts suspected of this disorder. However, it was reported that in patients with periodic limb movement in sleep (PLMS), this non-contact device overestimates the apnea-hypopnea index (AHI). We aimed to overcome this limitation by introducing the novel sleep disorder index (SDI) which is sum of the AHI and the period limb movement index (PLMI).