Assessment and measurement of cough: the value of new tools

On systematic investigation, patients with persistent cough are often diagnosed as having asthma, gastro-oesophageal reflux (GOR) and post-nasal drip; often, there is no associated diagnosis. Cough-variant asthma and eosinophilic bronchitis are conditions presenting with cough, usually associated with airway eosinophilia and responding well to corticosteroids. These conditions including asthma are best grouped as 'eosinophil-associated cough'. Analysis of induced sputum for eosinophils is an important tool in the investigation of chronic persistent cough. Reliable ambulatory counters for cough have been developed and the contribution of cough count and intensity to the severity of cough have been partly evaluated, and used in assessing antitussive therapies. Self-scoring evaluations are still widely used, but the inclusion of quality of life tools specifically adapted to the evaluation of cough appears to be a useful tool that can directly measure the impact of chronic cough. We need a greater assessment and evaluation of all these tools.