A new method for objectively evaluating childhood nocturnal cough.

Abstract

Cough is so common that the best method for evaluating nocturnal cough in children is required. We developed a cough monitoring system by evaluating 50 child volunteers, and validated the cough monitor in 20 samples from 10 children with cough overnight. Coughs were recorded using a video camera and digital sound recording. At the same time, our system with microphone and accelerometer was used. The number of coughs in each eight hour video-audio recording was counted manually by three trained observers, and all cough data were printed out and the defined cough events, using both these printed-out data and video-audio recordings, were then calculated by three observers. The cough monitoring system demonstrated excellent agreement between the number of coughs counted by volunteers, and those counted by cough monitoring system (sensitivity 98.8%, specificity 97.8%). Also, there was significant agreement in the counts of coughs between the video-audio method and our system (P < 0.0001), and between the defined cough events and our system (P < 0.0001). Our method demonstrated well agreement with the video-audio recording method in children, and is considered to be highly useful for the objective monitoring of overnight cough in children with respiratory diseases.