In this study, the RSpot is operated simultaneously with two other systems that provide a respiratory rate: Welch Allyn Propaq Encore model 242 and Embletta system with Universal XactTrace and Somnologica software. A respiratory rate is also obtained by counting respiratory excursions for the same duration as the RSpot measurement interval, 15, 30, or 60 seconds. The rates obtained from each of the four measurement methods are then compared.