Table 1

Cough definitions4 5 18

CoughA forced expulsive manoeuvre which starts against a closed glottis, associated with a characteristic sound.
Acute coughA recent onset cough lasting less than 3 weeks.
Prolonged acute coughCough lasting at least 3 weeks, which is ‘relentlessly progressive’ and may warrant early investigations.
Recurrent coughRepeated (greater than two per year) cough episodes that each last more than 14 days.
Chronic coughA non-resolving daily cough lasting longer than 4–8 weeks.4 18 There is no exact consensus on the duration in children.
Specific coughA cough with a specific underlying cause.