Children with chronic cough: When is watchful waiting appropriate? Development of likelihood ratios for assessing children with chronic cough

Abstract

BACKGROUND: Chronic cough is associated with poor quality of life and may signify a serious underlying disease. Diff erentiating nonspecifi c cough (when watchful waiting can be safely undertaken) from specifi c cough (treatment and further investigations are benefi cial) would be clinically useful. In 326 children, we aimed to (1) determine how well cough pointers (used in guidelines) diff erentiate specifi c from nonspecifi c cough and (2) describe the clinical profi le of children whose cough resolved without medications (spontaneous resolution). METHODS: A dataset from a multicenter study involving children newly referred for chronic cough (median duration, 3-4 months) was used to determine the sensitivity, specifi city, predictive values, and likelihood ratios (LRs) of cough pointers (symptoms, signs, and simple investigations [chest radiography, spirometry]) recommended in guidelines. RESULTS: Th e pretest probability of specifi c cough was 88%. Th e absence of false-positive results meant that most pointers had strongly positive LRs. Th e most sensitive pointer (wet cough) had a positive LR of 26.2 (95% CI, 3.8-181.5). Although the absence of other individual pointers did not change the pretest probability much (negative LR close to 1), the absence of all pointers had a strongly negative LR of 0 (95% CI, 0-0.03). Children in the resolved spontaneously group were signifi cantly more likely to be older, to be non-Indigenous, and to have a dry cough and a normal chest radiograph. CONCLUSIONS: Children with chronic dry cough without any cough pointers can be safely managed using the watchful waiting approach. Th e high pretest probability and high positive LRs of cough pointers support the use of individual cough pointers to identify high risk of specifi c cough in pediatric chronic cough guidelines. TRIAL REGISTRY: Australian New Zealand Clinical Trials Registry; No.: 12607000526471; URL: www.anzctr.org.au