Diurnal and seasonal variation of cough episodes in healthy young adults.

Setting: We developed an algorithm to assess recorded cough episodes and differentiate them from similar, non-cough sounds.

Objective: To measure cough episodes in healthy young adults, cigarette smokers and non-smokers over a 24-hour recording period, during the course of normal activity.

Design: The study subjects were students, aged 20-40 years old.