Pulmonary Pharmacology & Therapeutics (2002) 15, 267±272 doi:10.1006/pupt.2002.0360, available online at http://www.idealibrary.com on 1 Review Assessment and Measurement of Cough: the Value of New Tools K. F. Chung National Heart & Lung Institute, Imperial College & Royal Brompton Hospital, London, UK SUMMARY: 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. # 2002 Published by Elsevier Science Ltd. KEY WORDS: Cough, Cough variant asthma, Sputum analysis, Ambulatory cough counters, Self-scoring evaluations. INTRODUCTION Cough is a normal protective reflex essential for the clearance of the respiratory tract, but it may become pathological such that it impairs bodily functions and becomes an embarrassment for the patient. Loss of sleep, exhaustion, irritability, urinary incontinence, cough syncope, social disability, and inability to per- form daily activities may be associated with persistent cough. In many patients, cough may persist and become chronic in nature. Cough is probably the most common symptom after pain affecting humans and every human has probably experienced cough. Prevalence rates of cough have been variously reported as being 5± 40%, but cough is certainly one of the most common complaints that brings patients to consult their primary care physician. In secondary care practice, usually patients who have had a per- sistent cough for more than 3± 4 weeks are seen, and these patients usually undergo a set of investigations to determine the cause of their cough, so that treat- ment of the cause may be instituted. This often leads to an amelioration or resolution of cough. However, often, no obvious cause can be ascertained or treat- ment may not be successful. In such cases, the non-specific treatment of cough such as the use of centrally-acting opiates may be considered, although these may only be effective at doses that causes unacceptable side-effects. The management of chronic persistent cough has been extensively reviewed in the literature, 1±3 but this condition continues to pose a diagnostic and thera- peutic challenge. The `difficult' patient is the one where the cause continues to be elusive despite intense investigation and observations. Thorough investiga- tion is necessary and worthwhile. Common under- lying diagnoses on systematic investigation are asthma, gastro-oesophageal reflux and post-nasal drip. Other diagnoses such as bronchiectasis, chronic bronchitis, being on an ACE inhibitor for heart disease or hypertension, etc. may often appear. A percentage of patients will not have a diagnosis PULMONARY PHARMACOLOGY & THERAPEUTICS Author for correspondence: K. F. Chung, National Heart & Lung Institute, Imperial College, Dovehouse St, London SW3 6LY, UK. Tel: 44 207 352 8121; Fax: 44 207 351 8126; E-mail: f.chung@ic.ac.uk 1094±5539/02/$ ± see front matter 267 # 2002 Published by Elsevier Science Ltd.